A motorglider is under same rules as glider. You don't need a license to fly solo under supervision of a glider instructor. If you eventually want to carry a passenger then you need a FAA Private Pilot Glider certificate with a motorglider endorsement on your logbook. No medical. But must self enforce fitness to fly.
The USAF Academy had several Schwiezer 2-37 motorgliders.
My Grob G109 (avatar) is on the low end of purchase cost. $10k- 35k depending on condition.
Rutan designed his own "motorglider" for retirement.