Check with the dealer to see what, if any, "camping prep package" it comes with. Mine included the 25' power cable, a 25' potable water hose, and a 15' sewer hose.
10 gauge extension cord is nice to have. Extra potable water hoses of various lengths, extra sewer hose, too. Power adapters 15/20 to 30 amp (for home use), 50 to 30 amp (for campsites with overused/abused 30 amp jacks). I like to run a separate 12gauge power cable for outdoor camper use bypassing the TT 30 amp limit using the power pedestal's extra jacks. A power block or strip to go with that. A water pressure regulator can save your plumbing at rare but occasional high water pressure parks. Latex gloves for sewer pipe operations! Leveling blocks, I like the plastic Lynx ones that you can get locking wheel chocks for. Before buying any of the extras I mentioned, check pricing at www.walmart.com
and Amazon, usually noticeably cheaper than eBay or Camping World (unless on special sale). I use a bunch of 8-10" 2x6" or 2x8"wood blocks and 4x4" for various chocking of stabilizing and tongue jacks. I see in the pic the TT has those sturdy More Ryde steps. If the TT sinks into the ground or if the campsite slopes up on the door side, the steps will jam into the door bottom, major PITA. So check the step situation before unhooking or leveling the TT. I learned the hard way, doubling my efforts ;( I've had to rehookup and put my TT tires on blocks on both sides to get the steps to hang right to use the door! I installed exterior bubble levels on all sides to help with leveling.
Another camper in PA