Finally checked out Parkway Auto Exchange (Murfreesboro, TN) after seeing their lot on my commute for months. They keep around 64 vehicles, mostly 4x4 and off-road rigs. They were totally fine with my mechanic doing a once-over, which honestly settles half the trust question.
Lot address: 2980 Trailhead Rd, Murfreesboro, TN. Visitor parking: Front-lot customer stalls facing the office; overflow on the side street near Murfreesboro lot gate.
Paper side: licensed with the state (looked it up), about 78% of stock has title in hand per the office, and they offer a 30-day/1,000-mile powertrain warranty.
Overall: mixed feelings. Cars looked right but I got two different answers on a title question, and that's my personal tripwire. If you go, get the title status in writing before any deposit.