First cleanup engagement, client's books are a mess
I've been an accountant for 15 years, all of which have been at a $10m company with solid processes and clean books. This is my first real bookkeeping client (first stranger that is, I've done books for small businesses of friends and family) and my first time actually running a cleanup engagement rather than working with clean data from the start.
The client is bigger than what I'd normally start with as a first client, so I know I'm stepping into some unfamiliar territory here, but I'm confident in the technical accounting knowledge. What I don't have yet is a feel for the standard workflow of a cleanup specifically (not a catch-up since the transactions are already entered so just a cleanup).
The QBO file for 2025 is rough. Only the bank and credit cards have ever been reconciled, nothing else on the balance sheet. Just from a high level scan I can already see problems, for example a cash account (some sort of petty cash account) with a large negative balance. Another example is a large balance sitting in undeposited funds that's way more than what should realistically be in there. I know you might be wondering how the bank can reconcile with a large undeposited funds account, which is explained by duplicate payment entries, one via the bank feed and another one via the integration with the external AR software.
My question is: For those of you who do cleanups regularly, what's your actual process? Are you going transaction by transaction through the whole year, or do you focus on just correcting the issues on the balance sheet? I originally scoped the project as a full review of every single transaction (approximately 10,000 for the year) however the price came in very high and he is asking if there's anything I can do to reduce the scope of the cleanup so that its not a full review and more of a cleanup of just the balance sheet. Not sure how I feel about that as I'm a detail oriented person and so I'd prefer to review every transaction however I also understand that might be overkill (maybe, maybe not, your advice will be helpful here).
Just looking for any advice from the veterans out there. Thanks