I would not pay a high price for this, simply because people just do not say "cultivations" anywhere near as much as they do "cultivation" or "cultivate"
Here are the numbers on exact match:
[cultivation] 880 / 18,100
[cultivations] 58 / 260
[cultivate] 1,300 / 33,100
I would put it in the low-mid $xx bracket, and that probably where it will be for an end user too.
You may be able to get a small amount of adsense revenue, but it would need something on it for this to happen.
It is not enough just to have a keyword, it also needs to be a high value keyword and in the correct context and therein lies the hard part.
By the way, if you are wondering about buying a domain name I would not list it here or on any other forum, as anyone could swoop in and take it. Only post about it when it is in your possession
