It often comes down to how you know.  

Prices are so high and rents haven't kept up as well so if you're leveraging I'd be prepared to put down 35-40%.

Has anyone had success in buying down rates on single family with commercial loan?

They are not as attractive to bells and whistles but they have all the core functions down pat and then integrate with other software's for the guest functionality items.We had Guesty before and they had a lot of cool automations, but accounting was bad 3 years ago and we had to get the accounting down.Likely you will not find the "perfect" software you. 

Well, someone has to make a trip, or two, or three down to apply for and get the permits.

You are trying to take shortcuts today to save a few dollars and that is more likely to cost you a lot more down the road.

This is a great way to be able to put down a smaller down payment for an investment property. 

I will most definitely purchase a cost segregation study to nail down what I can depreciate at an accelerated rate.  

I am currently listening to Investing in Real Estate with Little or No Money Down...

I bought a duplex and have put $17500 down and paid $633 @ 2.5% for two years.