Toy hauler I'll assume 3 axle.
Leveling blocks 3 options.
1st - 2 or 3 2x6's long enough for 3 axles to sit on.
2nd - 3 or 4 packs of links levelers at $30 each.
3rd - 3 Andersen Levelers at $40 each.
Drinking water hose 25 foot- $25 to $60 X 2 depending on quality.
Sewer hose - 20 foot kit $45
So less than $300 for the basics.
After the basics you get into chairs, splitting maul, hatchet, pretty lights for the awning, extension cord, fan because the wife is miserable when she's hot, AWNING TIE DOWN KIT!!!, outdoor rug, pool noodle for slide out above storage door, fire poker, etc.
Edit: Adding wheel chocks about $8 a piece at Wally World for the yellow plastic ones. Check the date code on them. They do expire.
2021 Chevy Silverado LTZ 3500 Diesel
2022 Montana Legacy 3931FB
Pull-Rite Super Glide 4500