although only banks redline.. we just funded our first deal in Spokane yesterday so will see how it goes.. i did a flip there about 11 years ago did not go that well.. but the guy we had in charge was not experienced enough as it turned out. team now we have is uber experienced.

In my day our investors that were funding new origination's for fix and flippers in the bay area this was very passive.. 

Receipts for funds given?

they were in business 20 some years took in 100 of millions in due diligence fee's at 5 to 10k a piece.. there targets were newbie developers who had bigger complicated projects that no one would fund when you have little to no experience. 

They have used a hard money lender to renovate and are now out of funds.

That being said, assuming our next purchase is going to max out our DTI, should we prioritize purchasing the owner-occupied property first, and then look to unconventional funding/portfolio loan for the investment property?

.), and an idea of how you will fund a deal before making contact.

If we want to make an offer in the meantime, how do we show proof of funds and how soon do they expect the full payment.  

show all the states we fund investors in  and their product to hopefully help our Vendors sell more or BRRR more props with our help..  

It may be possible to obtain a funding using this method.