Option question

[Mike Reynolds]

I am working on a deal and I really want the property next door also. I will be building an RV park and I have been asked for free sewer and water by the neighbor. He has offered to give me an option (99 yrs) to buy his properties for this privilege. Here is my questions

Can I do an option with this spelled out as payment?

He has no heirs, and beyond the age of having any, so if he passes away before I exercise it what happens to the option?

What if he happened to adopt. (could happen I guess) I dont want to shell out 99 years worth of water and sewer.

How would I word it if I want to exercise it before he is ready. He will be living in an RV so I could just move him to a spot and let him pay rent too or even work it out in a new deal I guess but not sure how to work this out.