Finally checked out Gateway Motors (Wichita, KS) after seeing their lot on my commute for months. They keep around 140 vehicles, mostly late-model luxury cars. They were totally fine with my mechanic doing a once-over, which honestly settles half the trust question.
Lot address: 2896 Premier Ln, Wichita, KS. Visitor parking: Front-lot customer stalls facing the office; overflow on the side street near Wichita lot gate.
Paper side: licensed with the state (looked it up), about 88% of stock has title in hand per the office, and they offer a 6-month powertrain warranty on newer units.
Overall: decent cars, pushy back office. The $299 doc fee is fine but watch the add-on sheet — say no twice and the price comes back to earth.