I have never come across a campground that charges by the size of the RV - you pick the type of site you want - full hookup or electric/water only. The location of the site in the campground may or may not vary the price up or down. A back in site is usually less, but not always, than a pull through site. You pay the same for a Class B as for a huge Class A. And with my Class B I like it that way as I have been at campgrounds that want to put a Class B in the tightest space to save larger sites for the big rig that might come in - and charge me the same no matter what. I expect the site that I reserved and I know the rate before I get there - even if I reserved it that morning or the day before.
Price varies by location and how popular the area is. On the East Coast campsites seem to be coming out for us in our B in the $45 - $65 range. And these are not resorts - no pool, mini-golf, etc and we don't want that. We want a level site with properly working connections and service. I would love to find a decent commercial campground for $25 but that is not going to be around where we tend to travel. Go out into the middle of the country or head west and $25 to $30 sites seem common. Park campsites and the like will be less and may or may not have electric and water.
When looking for a campground I start with the epgsoft Campground Map website - find a campground in the area I want to be and then click on the link there to see reviews on RVparkreviews. Every campground of every type is shown on the map and scrolling around the map brings you to campgrounds further away. Most decisions are made on reviews and I may come to this forum's campground section for direct opinions. If you want free overnight camping there are sites to look for that also - and there are many opportunities out there - but you will not have hookups at all. If you travel on a budget you can spend a few nights for free and come into a campground for a night to dump and refill the water tank.
