>>174789215k is an insane budget to have for a van. With that money I would be looking at getting something that you can stand up in, fit a double sized bed in, 200 watts solar and 200ah deep cycle battery storage at least, at least one roof vent with a fan, a 45qt 12v fridge, propane stove and catalytic heater, and 20 gallons of water storage. Plan on using toilets at school/work/wherever, but have a 5 gallon bucket with a toilet seat lid, trash bags, and cat litter to shit in when you just gotta go. Pee bottles of course. You've said showers aren't a problem.
I've lived in a minivan, cargo van, and now I'm living out of a truck. I've never had 15k to my name at one time in my life, ever.
As a college student, law enforcement will tend to be a little more lenient. You can bet Utah and the western US as a whole is no stranger to van living. Just keep your rig clean and don't make a scene. Also, WalMart is the absolute last place you ever want to spend a night. Most of them contract cleaning of their parking lot out to fuckers that love to show up in the early morning and you WILL wake up to Jose and his leaf-blower rearranging detritus across the lot at 3am.
Vehicle life is pretty damn comfy. It allows a certain amount of freedom, but at the same time having all of your worldly possessions on wheels can be a bit stressful. Unforeseen breakdowns, theft, acts of god that a house might withstand, etc. can all weigh on the mind. For me, its the best way to live though, but I do have desires to carve out my own spot on this god forsaken rock at some point. There are so many resources out there to pull info from to help make your dream a reality. In a lot of ways college would be the best time to live in a vehicle.