PM me and I'll arrange an introduction with the one I use.

Maybe if you can give an example of what kind of an arrangement you're looking for it would help get you a better answer, I may just be I don't understand what it is you're looking for.

Your better brokers are performance based, which means that they don't get paid until you close a loan, so any effort you put into picking their brains will be well spent, and can lead to a mutually beneficial arrangement.

My question is what is the referral arrangement for ongoing referrals as we have a business relationship that has grown past the first deal?

Yes, owner financing is still a mortgage with terms that you arrange directly with the seller. 

Brokers who arrange loans will do most of the work with their own borrowers and sell/assign the loans to you.

Make sure you treat this like any type of business arrangement and that they have the ability to pay-that they have solid jobs/good credit etc :)3. 

Not because there's "no paper trail" but because there was no such arrangement in place.

Do an equity share arrangement where they get some of your upside whilst you still pay on your note or your renegotiated note.Pretty much what ever you the lender and you can agree on and makes sense for both parties.This is where you have to be careful of who you borrow your BRRR money from and you really should be all approved for the refi before you commit to PM loan or HML. 

I made arrangements with a partner to purchase the property using his cash.