Education costs money. Sounds like your niece and her husband got themselves an education. This is the main reason I bought an RV carport. I am still employed full time, so we only use our camper less than 60 nights a year. The other 300+ nights it is kept out of the rain, sun, leaves, snow, bird poop, etc. I still maintain, but if I miss something, its much less likely to have catastrophic results. Best $2400 I ever spent. I've had it for 10 years now, that's $240 a year for covered RV storage. We plan to be in this house for another 5 years, that'll drop it to $160/year for covered RV storage.
Our next house I plan to have a large metal enclosed barn so its completely out of the rain and out of the sun.