Seller keeping homes

Looking at a park with approx 80 spaces, 55 occupied. Of the 55 occupied, the seller owns 10. He is not including those 10 in the sale of park. He will pay lot rent and then rent out the homes.

The reason he is not selling the 10 homes is because of difficulty financing with POH’s.

I’m wondering if financing will still be dificult with a single tennant owning 10 units. Also I’m concerned with 20% of my rental income coming from one source. Has anyone else experienced this? Are there any other options? Am I too concerned about it? Should I be HAPPY to to collect lot rent from one person instead of 10? What’s my recourse if I raise the lot rent and this guy doesn’t want to comply?

Any thoughts?