Can A CPA Letter Reduce The Expense Factor On A Second Home Loan — The Quick Read: Yes, on a bank-statement (non-QM) second-home purchase — but only for business-account deposits, and only if the letter comes from a credentialed preparer who has actually reviewed the business’s records. It has nothing to do with a DSCR rental loan, where qualifying income comes from the property’s own rent, not the borrower’s bank deposits. Get the documentation order wrong and the file just falls back to the program’s default assumption.
Self-employed borrowers run into this constantly. They want to buy a second home, their traditional personal-income documentation understate what they actually make, so a lender turns to bank statements instead of a W-2 or a 1040. That’s where the expense factor shows up — and where a CPA letter can change the math.
What Is the Expense Factor, Exactly?
The expense factor is a percentage a lender subtracts from business-account deposits before counting any of it as qualifying income. It exists because a business account mixes revenue with the cost of running the business — payroll, rent, supplies, whatever it takes to keep the doors open. A lender can’t just add up deposits and call that income; some of it already went out the door to cover overhead.
Personal-account deposits usually skip this step entirely. Money moving from a borrower’s own business into a personal account also counts in full, with no haircut applied. The expense factor only affects business-account statements. It’s the single biggest lever in how much qualifying income a self-employed borrower ends up with.
How the Default Ratio Gets Applied
Across the wholesale programs Lendmire places files with, the default expense ratio is tiered by business type and staffing. It’s not a flat number for everyone. A service business with no employees typically gets a lower ratio than a product business with a full staff. That’s because underwriters assume overhead scales with headcount and inventory.
Without any supporting documentation, the file defaults to whichever tier fits the borrower’s business type. That default applies automatically — the underwriter doesn’t ask for permission to use it, and the borrower doesn’t get a say unless they bring something better to the table.
Where the CPA Letter Comes In
A CPA letter replaces the lender’s default assumption with a documented, reviewed figure. It does not let a borrower simply state a lower number themselves. The letter must come from a CPA, enrolled agent, or another qualifying tax preparer. That person must have actually reviewed the business’s books and filed its most recent return. This distinction matters: it’s third-party verification, not a borrower’s self-report. Compliance guidance built around this rule offers a close real-world comparison. A rancher’s own profit-and-loss statement can serve as a reasonably reliable third-party record — but only because an accountant prepared or reviewed it before the lender relied on it. The same principle applies here: an accountant’s signature makes the lower ratio acceptable, not the borrower’s word.
If the CPA’s review shows the business actually spends less on overhead than the default tier assumes, the underwriter applies the lower, documented ratio instead. Lower ratio means more of each deposit counts as income, which means a higher qualifying-income figure and, potentially, a larger loan amount.
Timing Is the Part People Get Wrong
The letter has to be in hand before underwriting locks in the default assumption. It can’t be requested afterward as a fix. The expense factor is a program-level input tied to documentation. It’s not something a loan officer can negotiate mid-file once underwriting has already run the numbers on the default tier.
Lining up the CPA letter early is, honestly, the single highest-leverage move a self-employed borrower can make on a bank-statement file. Waiting until after the file is already in underwriting to ask “can we lower this ratio” usually gets a no, or at best a delay while the letter gets produced and resubmitted.
When the Letter Won’t Help
Suppose the CPA’s honest review shows the business’s actual overhead is at or above the default tier. Then the letter won’t move the needle — it might even confirm the higher ratio. There’s no partial credit and no middle-ground compromise. If a borrower can’t produce a CPA letter or a profit-and-loss statement, they fall back to the standard tier for their business type, full stop. The regulatory logic behind every CPA-letter provision traces back to the ability-to-repay framework. That framework requires lenders to verify income using reasonably reliable records, regardless of documentation type.
Some programs also allow qualification directly off a CPA-prepared profit-and-loss statement instead of the deposit-based calculation — a separate path, run on its own basis, worth asking a broker about if the bank-statement math isn’t working.
This Doesn’t Apply to a DSCR Rental Purchase
A DSCR loan is reviewed primarily on whether the property’s own rental income covers its payment — subject to lender guidelines — not on the borrower’s business deposits at all. That means the whole expense-factor conversation is moot on a genuine rental purchase. There’s no deposit screening, no expense ratio, no CPA letter needed to prove income, because the income being measured belongs to the property, not the person.
This is where a lot of investors get confused, and it’s worth spelling out plainly: if you’re buying a property to rent it out and the rent carries the payment, you’re probably not the borrower this article is about. Lendmire’s complete DSCR loans guide walks through how that qualification path works from the ground up.
Second Home for Taxes vs. Second Home for the Loan
These are two completely different rulebooks, and conflating them is where investors get tripped up. For tax purposes, a home the taxpayer elects to treat as a second home can qualify even without personal use, as long as it isn’t rented out during the year — but if it is rented, IRS Publication 936 requires personal use exceeding 14 days or 10% of the days it’s rented at fair value, whichever is longer, for it to keep its qualified-home status.
Mortgage occupancy classification runs on an entirely separate track. Independent commentary on the term notes that the IRS defines a second home by election, mortgage underwriting defines it by occupancy and use restrictions, and FHA doesn’t use the term “second home” at all — three different rulebooks answering what sounds like one question. If the goal is genuine personal use with incidental rental income, a bank-statement second-home structure — where the CPA-letter mechanic is live — tends to fit. If the property’s rent is actually what’s carrying the payment, DSCR is the more honest tool for the job. That distinction, more than the CPA letter itself, is usually where the real decision gets made.
What This Looks Like at Different Loan Sizes
Second-home leverage through select wholesale programs steps down as the loan size climbs — the ceiling isn’t the same at $500,000 as it is at $3,000,000. On the smaller end of the range, purchase leverage on a second home typically runs up to 85%, with a 700 credit floor, through select lenders in Lendmire’s network. Move into the $1,500,000-$2,000,000 range and that ceiling holds near 80%, generally requiring a 700 credit score.
Above $2,500,000, leverage drops further. The $2,500,000-$3,000,000 band typically tops out around 75% purchase, with a 720 credit score floor. Once a second-home file crosses $3,000,000, lenders review it case by case before submission — there’s no flat “up to” figure. These files typically need 12 or 24 consecutive months of personal or business bank statements. The same expense-factor rule described above applies to the business-account portion of that income. Reserve requirements also scale with loan size. They generally move from a few months’ worth on smaller files up toward nine months or more as the loan amount grows. Add extra months for other financed properties. All of this is subject to full underwriting.
None of this changes because the letter exists. The CPA letter can lift qualifying income; it does not change the leverage ceiling attached to the loan size, and it doesn’t turn a $3,200,000 second-home purchase into a program with automatic terms. Every file above roughly $3,000,000 on a second home gets individual underwriting review before anyone quotes a number.
Loan-Level Scrutiny Is Real, Not Theoretical
This isn’t just a documentation nicety that matters only at the application stage. Loan-level data disclosed in securitization exception reports — including one SEC EDGAR filing for an asset-backed trust — tracks occupancy, DTI, DSCR, credit score, and LTV for each loan, for post-closing exception review. Income-calculation inputs like the expense ratio are exactly the kind of detail that surfaces when a loan gets reviewed after the fact. A documented CPA letter isn’t just about getting approved. It’s the paper trail that holds up if the file gets a second look later.
Key Terms Defined
Expense factor — the percentage a lender subtracts from business-account deposits to account for overhead before counting the rest as qualifying income.
CPA letter — a signed statement from a credentialed tax preparer who has reviewed a borrower’s business records, used to document a lower, actual-cost expense ratio in place of a lender’s default assumption.
Bank-statement loan — a non-QM mortgage program that qualifies a self-employed borrower using 12 or 24 months of deposit history instead of traditional personal-income documentation.
DSCR loan — a business-purpose loan that qualifies primarily on whether a rental property’s income covers its own payment, subject to lender guidelines, rather than the borrower’s personal deposits or traditional personal-income documentation.
Second home — a property classification that means one thing for tax purposes (an elective designation tied to personal-use days) and something else entirely for mortgage occupancy (defined by use restrictions the lender sets).
Frequently Asked Questions
Will a CPA letter guarantee a lower expense factor? No. It only lowers the ratio if the CPA’s honest review of the business shows actual overhead running below the program’s default tier for that business type. If the real numbers come in at or above the default, the letter won’t help — and might confirm the higher ratio instead.
Can I request a CPA letter after underwriting already started? It’s a much harder ask at that point. The expense factor is a program input the underwriter applies as soon as the file is reviewed, not something negotiated after the fact. Getting the letter lined up before the file goes to underwriting is the reliable path.
Does the CPA letter apply to personal bank statements too? Not really — personal-account deposits generally bypass the expense-factor step entirely, since a personal account isn’t assumed to commingle business overhead the way a business account does. Business-account deposits are where the ratio, and the letter, matter.
Is a CPA letter the same as a profit-and-loss statement? No. A CPA letter documents an expense ratio used inside the deposit-based calculation; a profit-and-loss statement is a separate, standalone qualification path some programs allow instead of the deposit method. They aren’t interchangeable, and a borrower should confirm which path a given program actually accepts.
Does this matter if I’m buying the property as a straight rental? Generally not. A DSCR loan is reviewed on the property’s own rental income, subject to lender guidelines — the expense-factor and CPA-letter mechanics are specific to bank-statement documentation on the borrower’s personal or business income, a different underwriting conversation entirely.
Tax treatment can depend on how the funds are used and how the property is held; investors should keep clear records and speak with a qualified tax professional before relying on any deduction.
If you’re weighing a bank-statement second-home purchase against a DSCR rental structure and want to see how the qualifying-income math actually plays out for your file, Lendmire can help compare options based on documentation type, leverage, credit profile, and program guidelines — reach out at 828-256-2183 or request a pricing quote to start the conversation.
For current guidelines and terms, see Lendmire’s super jumbo bank statement loan programs page.
About Lendmire
Lendmire, NMLS# 2371349, is a mortgage brokerage focused on investor financing, arranging DSCR loans in 39 states plus Washington, D.C. — 40 markets total. Qualification is based on the property’s income rather than personal income documentation, subject to lender guidelines, making it a fit for LLC-held rentals and scaling portfolios. Scotsman Guide named Lendmire a Top Mortgage Workplace in both 2025 and 2026.
Get Started
Ready to find the right loan for you?
In about 30 seconds you can review financing options available for your home or investment property. No commitment required.
Informational only. Not a Loan Estimate, approval, or commitment to lend. Program availability and eligibility are subject to lender guidelines, credit approval, property review, and underwriting.
References
2. AdviceOnly — “Second Home: Four Definitions, and Why Two of Them Conflict”
3. SEC EDGAR — EFMT Depositor LLC Form ABS-15G exception report
Brandon Miller
Founder & CEO, Mortgage Loan Originator, Lendmire LLC
- Mortgage Loan Originator · NMLS# 1129696 · Verify on NMLS Consumer Access
- North Carolina Real Estate Broker · License# 343312 · Verify on NCREC
- North Carolina Insurance Producer · License# 19053198 · Property, Casualty, Life, Health · Verify on NAIC SBS
- Lendmire LLC · Firm NMLS# 2371349 · Verify firm licensure
Compliance and disclosures. Lendmire (NMLS# 2371349) is a licensed mortgage broker and is not a direct lender, depository institution, financial advisor, or tax professional. Content in this article is general market analysis and educational information — not financial, legal, or tax advice for any specific situation. Lendmire does not guarantee loan approval; every transaction is subject to underwriting by the funding lender. Mortgage pricing and loan program guidelines are subject to change at any time without notice and vary by borrower characteristics, property type, and state regulations. Lendmire complies with Equal Housing Opportunity. Licensure verification: NMLS Consumer Access.
