We have a pretty large lot, .71 acre and are thinking about building a tiny/small house on the back side of our lot and renting our current house(3 bed 2 bath) either through airbnb or traditional tenants.

I've tried the traditional loan, but my credit is not what it needs to be.  

If I'm using traditional model for 1-3 units and outsourcing management at 10%, after collecting rent (let's say $1,000 per month per unit), mortgage, taxes, insurance, vacancy, maintenance and management, I should be able to cash flow around $300 depending on taxes at 100% occupancy.

1) The financial institute one has their primary mortgage with?

I plan to use a traditional 30yr fixed owner occupant loan.  

The Mrs. and I are looking to get a primary residence and I have been considering these floor types.

Which one is better: FHA or a traditional loan?

I don’t know the rules, but after much consideration we gave our contractor the go-ahead to do it on a remodel of our two story primary residence in Sherman Oaks back in 2004.

Currently, you can exclude up to $250K of capital gains on a primary residence if you own it and live in it for 2 of the 5 years prior to the sale. ($500K if you're married and filing jointly.)

We are considering modular or traditional builds.The problem:My partners and I manage a portfolio of property that spans multiple states and a variety of property types.