It sounds like you are looking to scale and get into flips!

@Enyo Kim meet like minded investors here:  https://www.biggerpockets.com/forums/521/topics/1228757-ocre...Good Investing...

Something between #1 and #2I know the answer is probably something like "however the numbers work best", but I'm looking for general guidance.

This will affect things like required down payment, rates, and even which lending institutions would be willing to finance. i encourage you to look up warrantability for financing just so that you don't have surprisses when your 20% down buyer cannot finance that way.

I like to look at all "deals" How did you find this deal and how did you negotiate it?

Rates are based on individual property characteristics like proximity to water, elevation, and risk factors.- Insurance Requirement: Flood zones still matter for federal regulations.

It sounds like that person is trying to wholesale the deal.

Are you just calling for the listing, or can you offer a free report for example 99 reasons why your home didn't sell or something like that.Don't forget to call the people who know love and trust you. 

List your property on corporate rental sites like Blueground, Zeus Living, and Furnished Finder to attract high-income tenants. 

It sounds like your question is what is the conventional guideline on using these rents to qualify ?