The first question everyone asks about cleanup is what it costs. The honest answer is that nobody knows until they've opened the file, and anyone who quotes a fixed price without looking is either guessing or planning to charge you for the surprises later.
That's frustrating to hear. So here's the next best thing: what actually drives the cost, how to estimate it yourself before you talk to anyone, and what a fair process looks like so you can tell a straight answer from a sales pitch.
What cleanup is
Cleanup is getting a set of books from wherever they are to a state where they close properly and a tax preparer can work from them without re-doing them. Sometimes that's three months of neglect. Sometimes it's two years, three abandoned systems, and a shoebox.
It's a different job from monthly bookkeeping. Monthly work is keeping a clean file clean. Cleanup is making a file clean in the first place, and it's the part of the profession where the estimates go wrong most often, because the mess is always slightly bigger than it looks from outside.
The four things that drive the cost
How far back. Every month that needs reconstructing is a month of transactions to categorise and reconcile. Twelve months behind is roughly four times the work of three months behind. Not exactly, because there's setup overhead either way, but close.
How many transactions. A consulting practice with forty transactions a month is a different job from a restaurant with four hundred. The count matters more than the revenue. A million-dollar business with clean, simple flows can be cheaper to clean than a small one with a card that gets used for everything.
How mixed. Personal and business in one account is the single biggest multiplier. Every mixed transaction is a question that needs an answer from you, and answers take time on both sides. If you've been running everything through one account for two years, expect that to dominate the estimate.
What state the previous work is in. Books that were never done are, oddly, easier than books that were done badly. Nothing done means starting from the bank statements. Done badly means finding what's wrong first, which is detective work, and detective work is slow.
How to rough it out yourself
Before you talk to anyone, you can get within shouting distance of the answer.
Count the months that need work. Pull one representative bank statement and count the transactions. Multiply. Then be honest about how many of those you could explain instantly versus how many would need thought.
A competent bookkeeper working through a clean-ish month with separated accounts might spend two to four hours on it. A mixed, messy month can take double that or more, and the first month of any cleanup always takes longest, because that's where the setup and the discovery happen.
Take your month count, take a realistic hours-per-month figure, and multiply by whatever the hourly rate is. That's your ceiling. It won't be exact, but if someone quotes you a tenth of it, they haven't looked, and if they quote five times it, ask what they saw.
What a fair process looks like
They look before they quote. Read-only access to the accounts, a proper look at the file, and then an estimate. In hours and dollars, in writing. If someone quotes without looking, that's the first sign.
The estimate is a range with an explanation. "Forty to sixty hours, and here's what's in the file that makes it that" is an honest estimate. "It'll be $3,000" with no reasoning is a number someone pulled from a pricing page.
Overages get approved before they happen. The mess is always slightly bigger than it looked. A fair process is one where, when the bookkeeper hits something unexpected, they stop and tell you before spending hours on it. If you've never been asked to approve an overage, you're either very lucky or being billed for it later.
It ends with something specific. A closed year. A trial balance that ties out. A file your preparer can inherit without groaning. If the deliverable is vague, the end date will be too.
Why cheap cleanup costs more
The temptation is to find the lowest rate. The problem is that cleanup done badly has to be done again, and the second time is harder because someone has to unpick the first attempt.
Most of the two-year messes we see aren't two years of nothing. They're six months of nothing, then a cheap fix, then a year of the cheap fix slowly falling apart. The cheap fix wasn't cheap. It was deferred.
We look at the books first, then put an estimate in writing in hours and dollars. Every invoice is itemised to the hour, and overages are approved by you in advance. We're not the cheapest option. We're the one you pay once.
The honest question to ask yourself
Is it worth it? Sometimes the answer is no. If a prior year has already been filed and the preparer was comfortable with what they had, re-doing it may not be worth the money. Cleanup should fix what needs fixing, not polish history for its own sake.
A good bookkeeper will tell you that. If everyone you talk to wants to clean up everything, ask why.