OP - In response to "I do not know their return policy. It isn't listed in the ad and when I click on RETURN POLICY on their website it just goes to the home page."
Caveat Emptor: Ethical 'bricks-n-mortar' stores have well defined and published transaction policies. Ask for theirs!
A.) If their policies ARE NOT published, shop elsewhere - period (If it seems too good to be true, it probably is.). Weather buying New or Used, work with shops that are transparent and that you can trust...
B.) If their policies ARE published, make a screen-capture of them (just in case...), and those policies include a 30-Day trial, use your credit card for the purchase. If something goes sideways, your credit card company will want to see those policies before they can provide your buyer-protection.
Finally, +1 - Testpliot: "it is incumbent on the dealer to develop relationships."