To make things even more confusing, each company presents data in its own format.They use different assumptions for down payment percentage, interest rates, loan tenure, and expenses.

I had specifically asked for numbers including mortgage payments and they emailed to me.

Have you considered tapping into your existing rental equity for the down payment?

Most hard money lenders require 10-20% down payment of the purchase price or total project cost.Holding Costs During Rehab: Yes, you'll need to cover carrying costs, including hard money interest, utilities, taxes, and insurance.

Gave me the monthly payment and I checked it against a mortgage calculator and it's exactly what that said. 

You likely only made a down payment of 3-20% ....but you still get to write it off on the full value across 27.5 years.So 400k/27.5 = 14,000 ish a year of a write off where during the year you didn't need to incur an actual expense, no cash outflow. 

Know that every long term lender will require a survey and if something comes up on it when you are trying to sell or refi, you could get stuck in hard money without an easy or quick way to get out.Is there a pre-payment penalty?

Let your criteria do the filtering for you.Regarding retention and renewals, the only time I have asked people to leave is when they have had rent payment issues and/or damaged the property. 

For some buyers it would end up being less than a 2.5-3% commish, and for others more.The tricky part for the buyer is it would have to come out of their pocket in addition to the down payment, whereas a commission paid by the seller at closing is included in the purchase price and absorbed into their loan (usually unless paying cash obviously) so the buyer only has to make the down payment out of pocket.

Then the rents would cover that payment plus the mortgage with cash left over.