Share 'RV's and Seasonal Jobs'

I'm an older guy (62) who has worked one year in Yellowstone. I've read that some jobs allow you to live in your RV. I don't know a lot about RV's. Can anyone recommend what kind of RV I might consider specifically for seasonal work in the national parks? My needs are modest and I would buy or rent a used RV if that is a reasonable thing to do.