I don't mind doing the accounting the first week of each month but I'll be danged if I'm doing this every day!!!

You can design your form any way you want to as well.Let's take a look at a typical Rental Invoice.  

They even assign categories on their invoices to help streamline your A/P entry coding.

You can share documents (invoices, quotes, spreadsheets), make video and voice calls... it does it all.And no I do not work for them or have any affiliation, Im an IT professional / house flipper who just thinks it would be a great solution.Good luck!

I  have many months my  invoices go over 10 k for repairs, rehabs, checkouts, etc I do not even inspect the work, it can wait for the annual inspection.   

.- Ask Contractors to invoice you NOW for work they have done or are about to do.- Pre-buy construction materials maybe even some storage to put them in- Buy tools for you or your contractors to use on a future flip - Hire an accountant to help with some of these ideas

It's been debunked on here several times as pretty dang unethical.

As they do not have any money to claim back they just leave and trash the property and then I go through a major number of repairs, the only advise that the PM is suggesting me is to get the invoice and send this to 'collections' but I never see this money back.

@Ian Lord Yes send an invoice with the 5 day pay or quit stating that they owe the remaining X amount with your late fee and follow through if payment isn't received.

We also delivered an invoice along with a copy of the water bill for the $55 of usage that I paid for and told them they could remit payment with their following month's rent (1 week later).Rent came this month and they didn't include it.