@Craig PoskusYou're conflating two different expensing safe harbors.What you're describing above is the safe harbor for small taxpayers (SHST), not the de minimis safe harbor (DMSH).There is no gross receipts limit or unadjusted basis limit regarding the DMSH.Note that the $2,500 limit under the DMSH is on a "unit of property" basis, not an "individual line item on an invoice" basis.If that seems complicated it's because it is. 

Enter a maintenance request, assign a vendor, attach a fake invoice.

It's easy, convenient, helps me create invoices, send reminders, and manage payments for multiple guests at once.

Long and short of it I have gone through 3 months of accounts with the current property management company any found discrepancies where there are several duplications of invoices for the same work done within a few days of each other, invoice totals slightly varying. ie.

If that's the case, the de minimis safe harbor of expensing anything under $2,500 per invoice or per item may apply. 

My advice to you would be (1) Start a separate LLC, (2) Get a GL policy for that LLC, (3) Get a management platform - I use Buildium, (4) don't co-mingle client's funds,and (5) be transparent with your client on all invoices and work orders.

Then expect at least another 30 days for a final financial accounting with all received invoices and payments accounted for.

Get written estimates (or actual invoices if work has been done) from third party contractors for all repairs needed due to failure to properly report the leak to you.

Further, instruct them to immediately turn over all tenant Security Deposits; to cease any actions to modify, replace, or terminate existing rental agreements; provide you with copies of the existing rental agreements; turn over all keys in their possession and lock combinations; provide you all unpaid and outstanding invoices currently in their possession; and to provide individual tenant ledgers for all of 2022 and 2023 to date.

Enter a maintenance request, assign a vendor, attach a fake invoice.