We stayed 1 night in a 37' motorhome. As others stated, the lot is slightly sloped but it's very quiet & we felt very safe, even on a busy Friday night. Lots of other RV'ers. Some small rigs parked on the graveled section alongside the paved lot most likely because it was more level there.
If you sign up for a Player's Card, they give you $10 in cash to use as you wish. Buffet breakfast was $5.95 for 55+years; $6.95 otherwise. Entry level Player's Card will also get you hotel room if you want for $29.95 (regular rate $119 weekend; weekday $79); mid-level Player's Card $19.95/night; high-level Player's Card free room.
There's a Safeway supermarket a block from the main road (US-95). There's also an RV Park (not associated with Casino) adjacent to casino - full hookups $25/night; monthly $342. We definitely would dry camp at Blue Water Casino again.