A large hotel will cost a lot more than a small one. There aren't any for sale right now.
Do you mean a ROOM at a hotel in Cottonwood? You'd need to find out what the room rates are for every hotel, add it up and divide it by the number of rooms you added up - that's how you find an average. If you want to know how much rooms go for in Cottonwood, go to one of the "usual" travel websites and look it up. Travelocity, Expedia, Orbitz, etc. all have that info.
there are quite a few sites that you can search that will likely show you great hotels at the best prices available. check out the website BookMe and you will be able to compare prices on all the reputable travel sites in just a couple minutes. it's very convenient and will save you a bunch of time and money. Also, make sure you buy them online... otherwise they charge much higher fees for phone orders. good luck.