I have made 44 online purchases. Most were from GunBroker, some were directly from vendors, and a few were from the CMP (Civilian Marksmanship Program). The purchases were a mix of new and used guns.
I inspected all of the guns (except CMP rifles) at the transfer dealer before accepting the transfer. It was a hoot receiving the CMP rifles at my front door and I obviously could not inspect them before acceptance.
One purchase of a gun listed online by a local store was a bit odd. When I went to the store, the gun was priced substantially higher than online. While inspecting the gun, the clerk whispered I could step back, order the gun online at the lower price, and then go to the cashier to pick up my purchase.