Interesting that this seems to cover all property zoned residential, with no apparent carve out for a transaction of residential property between two investors.  

Most lay people have zero idea how to get through a transaction.

Don't trust what ANYONE tells you about a market without solid data to back it up - this includes claims about how many transactions they've done or a single example (that's often from several years ago). 

If I have specific questions about a transaction I’m doing or something like that, I just ask via email or phone call.

If anyone has any experience on either end of a transaction like this i would be interested in hearing from you.

So, those of us who ask the correct question can safely ignore the "velocity" part of trying to pay off our low interest rate mortgage, in favor of putting any extra money we have into buying extra assets that (also) return a higher interest rate / appreciation (just like our primary has already been doing).HELOCs help us do that, so why are you in hurry to have zero balance owing? 

I would suggest giving it up and just hire an agent when you are ready to transact in the future.

How exactly does transactional lenders work?

How do you navigate the wholesale transaction when buyer is wanting to use traditional financing?

If you have a willing seller with a willing buyer doing creative financing, it's the  simplest of transactions.