Typically how i do it is this.
1. Put up an ad on Craigslist or find relevant buy/sell/trade groups on Facebook or relevant bike model specific groups
2. Arrange a meeting time and place (i prefer daytime and a public place like a gas station or a walmart parking lot)
3. Go through sale procedures
4. If buyer wants a test ride, i need something of equal value in my hand. Car keys, wallet, cash.
I haven't run into any issues with non endorsed people wanting test rides, they will typically disclose if they don't have a license or are looking for a first bike or will ask you to ride it for a minute around the parking lot so they can see that it moves.
5. Close the deal or walk away,
6.
7. Take the money and head to the club.