Question is whether you want to pay a higher rate for that flexibility. 

You can be very flexible in how you write the terms, but they can involve a down payment, higher than regular lease payments, and a "credit" from those 2 things when they're finally ready to officially purchase it by exercising the option.

These aren't backed by the GSEs like Fannie/Freddie and instead rely on secondary market investors so the rates are certainly higher but figure there are several other advantages besides the ability to vest title in an entity such as no DTI requirement (based on DSCR instead), no tax returns needed, no limit on the # of financed properties you own, general underwriting flexibility, etc etc. 

I know there's a one-year period where an owner must occupy their FHA (3.5% dp) purchase, but curious how flexible that is.

You need to prove you are an asset to the bank and are a sure thing to pay back loans, then you can get more flexibility.5+ you will need a commercial lender.  

Sounds like lenders will be flexible enough to accommodate my situation.And you're right about the price range.

Rentals seem a natural fit for this as a long term strategy, but in my experience a balance of flips and rentals allows for a bit more flexibility.

That way I would have the flexibility to leave when I want and rent it to an actual tenant.

Once a tenant proves to be one we want to keep, we leave them the flexibility of M2M.

However, if you are clear on your goals while maintaining flexibility in your strategies, you can make it happen.