Better gas mileage

Starting to make sense. I've been doing some research and realize that the gas mileage really isn't what we should be factoring in here. It's only the two of us, maybe an occasional trip with our adult daughter, but we're planning on retiring in 6 years so we need to focus on how much room we need. I used to do a lot of camping with my young kids in a tent trailer, even lived for 6 months in a truck camper so I'm used to the organization that's needed in a small space. My husband, on the other hand, isn't so it's more trying to come to a compromise. We're only able to deal with an amount of $10,000 for a used class c, so that's why we're researching everything. I've done a lot of reading in the forums and finally bravely ventured forth to ask what is so obviously a newbie question. Thank you for your patience and willingness to lend your wisdom. It is very much appreciated!