I like my Husky Centerline WDH. $400 new is a decent price. They should perform the initial installation, watch them to understand how it is done and review the manual to see how well they followed Husky’s instructions. Make sure the WDH is rated for the range of the TT GVWR & 15% of that for tongue weight rating. It’s not rocket science. You do need some big sockets and wrenches and a flat level spot for measurements. My dealer had a concrete pad extended out from the concrete shop floor for this. This hitch is NOISY on right angle turns, sometimes sounds like breaking metal! Great sway control in winds.
Get the list of items in the starter kit. You can price them out on Amazon or even Walmart.com. I’ve normally seen the starter kit included in the negotiated sales price of the TT and not a separate line item.