You’d have to winterize the plumbing in winter. Toilet could still be usable if you flush with RV antifreeze. Would have to take showers at a gym in the winter. If you’re going to the gym daily anyway, that’s not such a bid deal. For someone without experience using RVs, might not be worth the effort but I used to have a couple RVs and would go this route just because it would be ‘my’ space. Plus side is that if you get one that is ‘used enough’, you might get what you paid for when you sell it.

In the summer though, full plumming would be available which would include showers in units that have them. But even that’s not without inconvienience... you still have to find a place to dump and refill every so often. In my experience, those labeled ‘conversion vans’ usually don’t have showers. Units labeled ‘Class B’ which are built on the same frame often do. Look for one’s that are 19’. Anything bigger will ‘officially’ need more than one parking space (though you might be able to make one slightly larger work by parking with the back end hanging over curb/sidewalk/grass).

Also, none of these will park in a typical airport parking garage (too tall). If you’re airport has a parking garage for the employee lot, don’t bother.