I said I'd pay for what he did but he only sent a $700 invoice for "Inspection", which I said I'm not paying unless he tells me what he did.

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

I have done what I can to automate things- invoices go out automatically each month and mortgages get paid automatically as well, and my time spent is extremely variable since we don't hire much out- we do the maintenance, cleaning, snow, lawns, leasing, etc.  

I invoice on the 20th of the month and have them mail to a PO box. 

Operating is for receiving rent, paying invoices, paying your management fee, and paying the owner.

It allows them to make their money and then I simply invoice at the end of the month- so I'm not in charge of their money- they like that. #2 It allows each individual property to have it's own review- so if they do want to leave- they can keep their reviews in tact. 

I wouldn't have responded to them, personally, since they didn't even send the invoice to you directly.

I'm not sure if it's necessary, but I like to have all the invoices for all my maintenance and repairs.

I am an investor and a CPA with clients investors.I use Quickbooks to manage my investments and it works - so far :) it also has invoicing and payment automation, however, you need to add the extra expenses (a repair) and this will happen with any software. 

I buy a new pick up I drive it at least 10 years or more.I never have leased a pickup truck seems crazy from the math.I use to buy at invoice price, the dealers caught on about that so now invoice price numbers are pumped up leaving the buyer access to the true numbers muddle with false invoice prices.I would read Clark Howard on this topic very good read.https://clark.com/cars/eye-opening-truth-about-dealer-invoice-price/