Welcome.
At the very least take some scrap 2 x 4s or 2 x 6s with you to level the camper, you don't have to have a BAL but many here like them. Another option are the Lego-like orange blocks (various brands).
Start with "camp driveway" for a night, that way you can grab things from your house as you find you need it. Make sure you have a dump tube and white water hose (NOT a green garden hose) for the first trip out.
You don't need a 50-30 or 15-30 adapter the first trip out, but definitely get them soon because the day will come when you find there isn't a 30 amp plug, or the 30 amp plug is wired wrong, or just bad from too much use. Then you'll need one of those adapters. Also make sure to get a 50 foot 30 amp RV extension cord.
Speaking of bad wiring, go to the link in my signature and check out the first item on the list.