Seattle Due Diligence Accountant: 5 Questions to Ask First

Seattle Due Diligence Accountant: 5 Questions to Ask First

A Seattle due diligence accountant tests whether the business you are buying, or selling, is what its financial statements say it is. The fastest way to find out whether an accountant can do that is to ask five questions before you hand over a single bank statement.

The numbering below is a sequence to work through, not a ranking.

On the Sam's List partner roster for Washington, one partner lists a Seattle base: System Six, a bookkeeping and fractional CFO firm. As of the roster's last update on September 14, 2026, that is the only Washington-based partner, and System Six is written up below. System Six is a vetted Sam's List member and a paying member of our featured program; payment does not buy the language we use or its reviews. You can read the methodology at the end of this post at the end.

1. Does Your Seattle Due Diligence Accountant Prove the Cash Before Trusting the Profit?

Ask whether the accountant runs a proof of cash. It compares the bank deposits for a period to the revenue the books report, and the bank withdrawals to the expenses. A direct answer is yes, for at least the last twelve to twenty-four months, with the differences listed and explained.

Profit on a statement is an opinion. Cash in the bank is harder to argue with. A seller whose revenue is higher than the deposits can explain, or whose expenses are paid from a personal account, will show up here first.

The limitation: proof of cash finds timing gaps and unrecorded transactions. It does not test whether the revenue will repeat, and it cannot rebuild records that were never kept.

2. How Will You Treat Add-Backs, and What Proof Do You Need for Each?

Add-backs are adjustments to a seller's profit, such as the owner's above-market salary, a one-time legal bill, or a personal vehicle paid by the company. They turn reported profit into the "adjusted" figure the asking price is built on.

Ask how the accountant classifies each one and what documents support it. A buyer should expect to see an invoice, a contract or a payroll record behind every large item. A seller should expect the same questions, so gather the documents first. An accountant who accepts add-backs on the seller's word is not doing diligence.

The limitation: judgment is part of it. Whether a cost is truly one-time or only irregular is an opinion, and two careful accountants can land on different totals.

3. What Is Your Financial Due Diligence Checklist, and What Do You Leave Off It?

A financial due diligence checklist is the list of what the accountant will review. Ask to see theirs before you sign. A sound one covers revenue by customer and by month, the quality of the receivables, accounts payable and unrecorded liabilities, payroll and contractor classification, debt, inventory if there is any, and tax filings.

Then ask what is not on it. Some accountants do accounting diligence only, and leave legal contracts, licenses and employment questions to an attorney. Others offer a full quality of earnings report, which is a larger and costlier engagement. Neither is wrong. The problem is assuming one covers the other.

The limitation: no checklist finds everything. Diligence samples and reasons from the records offered. It reduces the chance of surprise and does not remove it.

4. How Do You Set Working Capital in a Seattle Business Sale?

Working capital in a Seattle business sale is usually settled by a target in the purchase agreement: the amount of operating capital the business is expected to deliver at close. If the closing number is lower than the target, the price can go down. If it is higher, it can go up.

Ask the accountant how they would define working capital for this business, which periods they would average to set the target, and which accounts are in or out. Cash, debt, seasonal inventory and customer deposits are the usual fights. Defining them in the agreement matters more than the arithmetic.

The limitation: a working capital adjustment is a negotiation as much as a calculation. The accountant can model the numbers, but the contract language decides how the adjustment works, and an attorney should draft it.

5. What Do You Know About Washington B&O Tax, Seattle Taxes and the Deal Structure?

Washington charges a business and occupation (B&O) tax on gross receipts, which means revenue rather than profit, so a business can owe it in a year with no profit. The City of Seattle also has its own business taxes, including a payroll expense tax that applies to larger payrolls. Whether any of these reaches a given business, and at what rate, depends on revenue, payroll and activity classification, and the figures change.

Ask the accountant to review the target's state and city filings for unpaid or late tax, and ask how they would look at sales tax collected in other states. Then ask what they will leave to your CPA or attorney. Whether the deal is an asset or a stock purchase affects which tax history follows the buyer, and Washington also has a capital gains excise tax that may be relevant to some sellers. Those are questions for a CPA or attorney, who decide what applies.

The limitation: some bookkeeping firms do not prepare tax returns at all, so confirm scope in writing before assuming a tax review is included.

Where System Six Fits for Seattle Buyers and Sellers

System Six is a bookkeeping and fractional CFO firm based in Seattle. It was founded in 2009, has 41 employees and serves clients nationwide. Its live profile says it serves businesses generating between $1 million and $10 million of revenue, lists Non-Profit Organizations, Professional Service Firms and Real Estate Investors among its specialties, and says the firm was acquired by a searcher in 2021 and helps organizations modernizing a finance function after an acquisition.

That makes it a fit for the stage after the deal: clean monthly books, reports a new owner can trust and a finance function that stays in place once the advisers leave. Clean books also help a seller, because buyers' diligence goes faster when the records are easy to read.

System Six does not yet have enough verified reviews on Sam's List for us to cite a count. Ask for references from owners who bought or sold a company.

The limitation, plainly: the profile does not list transaction diligence, a quality of earnings report or tax return preparation as services, so ask whether any of that is included. The profile also lists a $1 million revenue minimum, so a smaller business may fall outside what the firm takes on.

How to Compare a Seattle Due Diligence Accountant on Scope, Deliverable and Timeline

Whatever you hear from any firm, ask for three things in writing: the scope (which questions the accountant will answer), the deliverable (a memo, a spreadsheet, a full report) and the timeline (days from receiving records to a draft). Diligence runs against a closing date, so a firm that cannot start for three weeks may be the wrong firm for this deal.

Compare how each firm answers the five questions above. The best signal is a specific answer with a stated limit.

Frequently Asked Questions

What does a Seattle due diligence accountant do?

A Seattle due diligence accountant reviews a business's financial records before a sale. Typical work covers proof of cash, revenue quality, add-backs, working capital, debt and tax filings, delivered as a summary of findings. Scope varies by firm, so get it in writing.

What belongs on a financial due diligence checklist?

Revenue by customer and month, bank statements matched to the books, receivables and payables, payroll, debt, inventory, tax filings and any unrecorded obligations. Add the contracts and licenses an attorney should review. No checklist replaces judgment about what the records are leaving out.

How is working capital handled in a business sale?

The purchase agreement usually sets a working capital target, and the price adjusts if the closing amount is above or below it. Definitions and the period used to set the target matter. An accountant models it, and an attorney writes the contract language.

Does Washington B&O tax matter in a business purchase?

It can. Washington's B&O tax is charged on gross receipts, so unpaid or late filings are worth checking. Whether a buyer inherits an obligation depends on the deal structure and state rules. Ask a CPA or attorney, and confirm details with the Washington Department of Revenue.

How We Picked This Firm

The pool. The pool is the Sam's List partner roster for Washington. As of that roster's last update on September 14, 2026, the only Washington partner on it is System Six, which is based in Seattle, so the write-up covers the whole roster. This is not a survey of every accountant who serves Seattle business sales, and many firms outside the roster could fit.

How it is organized. The five questions are a sequence to work through, not a ranking. System Six is the only firm written up, so there is no order of firms.

What review counts mean here. System Six has too few reviews on Sam's List for a count to mean much, so we do not cite one. A count shows how many clients wrote something down, not quality.

What payment does and does not buy. Listing on Sam's List is free, and so is being named in this article. The firm written up here is a paying member of our featured program, which is why it gets a write-up. What payment does not buy is the language we use about a firm, its review count, or a promise that it fits you.

Before you hire anyone, write down the three numbers you most want proven, and ask each firm how it would prove them. You can browse fractional CFOs on Sam's List, including System Six.

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About the author: Kimberly Green is the cofounder of Sam's List, where business owners and high earners find vetted CPAs, financial advisors, and fractional CFOs. She's met one-on-one with 400+ financial professionals and writes from the real data behind thousands of client-advisor matches. Ask her anything about finding an accountant - she's heard it all, including the questions people are afraid to ask.