This website should give you some information. www.NADAguides.com The prices depend on what options the RV has and the condition. Be sure to refer to the previous posting checklist on what to look for in a used unit. Check the usual places such as ebay.craigs list for used units.
Check out the brochuers . Should be able to answer most of your questions. Pecking order is pretty much a personal perference. It all depends on what you are looking for, how many you want to sleep, features....