We want to purchase a rv that will be short enough to park so we dont have to tow a vehicle. This would be used for short trips. We would like to park in a parking lot across two spaces? What is the longest we could use? What about if we decided to go with one that we could park in just a regular parking spot? We are thinking class c would be our best bet? Also, we are looking at older used rvs and have been told that the ones with overdrive and fuel injection have better gas mileage and less mechanical problems? How do you tell if they have this on an older rv? Thank you so much for your help. We are trying to learn.