Then the invoice is attached. 

I have sometimes seen owners give the prop mgr 10% ownership to have a little skin in the game but they are usually contractors that do a little more than just invoice and collect rents.

You could integrate with Zoho CRM, and it'll work very well especially for invoicing or sending estimates, etc.

I'm no invoice, but each deal is an adventure and sometimes bumpy roads will occur. 

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

@Mary Jay, to layer on to Connor's comment, while some lenders will only pay draws on invoices paid with lien releases, there are also some that will allow you to submit draws on invoiced work.  

First check your state laws regarding security deposits.If we have a tenant that trashes a property, we cannot just automatically forfeit their security deposit and we have 30 days to send the tenants an itemized list of charges against their deposit.In Texas if an owner does not follow proper procedure even though the tenant trashed the property, the tenant can go back after the owner for triple the security deposit plus attorney fees and court costs.If you accidentally did not follow your state laws, I would immediately refund the total deposit.If you followed your state laws, then you should have at least contractor invoices for the work done to justify the expenses against her security deposit.

 $.50 per transaction, you can send invoice automatically, they can pay automatically.  

I'll send a paypal invoice shortly.

If there is not invoice, then that should be the end of it.