I have a client who needs to file 2022, 2023 and 2024 1120s. And has the following issues:

1. They did not pay reasonable compensation for any of those years.  Is there anything you can do to rectify this for prior years? Salary will resume this year (2025) 
2. The previous preparer had an amount in Loans from Shareholder, which has increased each year as the owner "loans" money to the corp.  Today the total sits at about $135,000 with only one payment of $25,000 made in 2023. There has been no loan agreement or interest paid.  Bookkeeping was also not kept for any of the years.  Now this year they want to treat the Loans from Shareholder as a bona fide loan and start paying interest.  Can this be done? Or would it be recharacterized as additional paid in capital? 
3. They also have roughly $35,000 in distributions each year from using business accounts for personal expenses.  Distributions exceeded basis in 2023 and 2024.