They're not that bad of a person, and seem to be conforming to regular society.

However, every lender I’ve applied with so far won’t do a loan amount over $780k (which I thought was odd as I would have expected any such cap to be $765k, the conforming loan limit in this area).Do you have experience doing a jumbo cash out refi? 

I'd definitely suggest a small multi-family (2 - 4 units) for several reasons.1) Can be purchased with a conforming loan2) Ability to house hack (if desired)3) Vacancies don't decimate cash flow4) Potential net cash flow higher than that of SFRSome important things to think about. 

Most loans out there are convention / conforming loans that conform to Fannie Mae / Freddie Mac guidelines.  

Where I invest, you can split 1 property into 3 quite easily as long as the new parcels conform to zoning standards.

That is an exemption in the freddie fannie underwriting guidelines, so any traditional conforming lender can offer.

Your lender is probably only familiar with conforming fannie mae/Freddie mac loans. 

It all depends on the location, type and size of property Fisrt step is to meet with the city to find out if there are any code issues and non-conformities.

If your strategy is BRRRR, which is heavily reliant on financing; it's more important to save hard credit inquiries and maximize your number of conforming loans before going commercial, portfolio or hard money lending options.

The 4th bedroom is in the basement so it's non-conforming (you can't really market it as a 4 bedroom legally).