I personally don't want to use them again mainly because of the lack of communication 

The materials are outstanding and my understanding pre covid the networking and in person classes where very beneficial .

Obviously you tell this person that “only trusts you” to sell and pay the taxes and pocket $50k minimum more than selling to you.

nothing pointed at you personally but there has been build to rent projects were investors had to put up 50k non refundable and never got their house built.. so I can see putting it in escrow and releasing it upon closing for sure.. thats what i personally do with my new builds although since we average 25 to 75k of upgrades per house buyers have to stroke non refundable checks directly to us for those items.

Be careful of the advice you get from unqualified persons here or in any forum.First. 

Also, do you rely on Virtual Assistants or full-time staff to handle comms and requests?

We talked for several minutes, then out of the blue he said he would offer seller finance if he found the right person to sell to.

I found that actually talking networking in person or the very least a Zoom call much more helpful.

I picked up another duplex for my personal portfolio that will bring me to 14 doors.Who do you use for property management?

Your Realtor will be your go to person the entire time.