I currently own two .us domains that I have out on a lease with option to buy program. When I was approached about the names (by two different buyers) I had a price tag of $1,000 each on the domains. I told the buyers they could own them immediately for that, or I would lease them to them for $100 a month for 12 months ($1,200 total) and would transfer ownership to them at the end of the 12 months if they made all payments on time. Both took the lease arrangement.
Under the agreement, if they stop making payments at any time, all previous payments will be considered rent and I retain ownership with their rights then relinquished. I simply changed the nameservers to the ones they wanted to use after they made their first payments. Both buyers have paid steadily on time and they will gain ownership by the end of the summer.
This is an attractive plan for many small businesses who can afford the monthly payment more easily than paying the lump sum up front and you earn 20% extra for letting them carry it for a year - not a bad return in today's financial market - especially when there is no risk to you - you just change the nameservers back to your own if they default.