Business Accounts Advice / Check 2yrs of Accounts

I have used an accountant for my business accounts for a number of years, however I think he has made some errors and not accounted for certain things correctly (namely director's loans and some investments / losses made).

I'm after a second opinion on 2 years of completed accounts and some queries on these addressing.

Should there be issues then this will likely lead to further work in correcting these and resubmitting, as well as completing current year's accounts and a number of years of personal tax returns for 2 directors. Price for these can be negotiated separately after this job.