1)If shopping for an RV on a budget, then really look at the features. Think if you really need the feature or if it's just something nice to have. Then figure out how often you would ACTUALLY use that feature. Not that you think you would use it, but that you would actually use it. For example: our first travel trailer was a 31' model. 35' total in length. Had to get an F250 to tow it. Nearly 8k lbs dry. 11k lbs max. Had 4 bunk beds. We have one kid at home. We just knew that our daughter would be bringing friends, thus justifying us having to have a bunkhouse. in 3 years of having the TT, 2 of my nieces ended up staying with us one night. Many other nights, my daughter slept of the sofa. Was a big waste of space.
2)Buy the smallest unit you can stand. The fact: if you can stand to be in small quarters for periods of time (sleeping, inclimate weather), then the better you will be. Generally speaking, it will probably cost you less (but not always). It will be easier to tow and to park. You will also have many, many more campsites to choose from. Especially if you like to camp in Federal or State Campgrounds.
3)Spend money on your ability to be self sufficient. More batteries, inverters, solar, larger holding tanks, etc. Why you may enjoy the resort with it's full hook ups and amenities, you may end up wanting to enjoy some places with better views and no hook ups. My wife is finally leaning that way now.