You can do a reference check on the buyer. unfortunately nowadays, scammers are constantly coming up with new techniques and it pushes away potential buyers, new collectors etc.
All the above is sound advice. dont forget:
check return policy,
if wiring money, you better wire it to the seller himself, not someone else.
I dealt with a few sellers here that were honest, no cheekiness etc. so thats great.
I came across this video on youtube which I found interesting.... Good luck.
https://www.youtube.com/watch?v=CQeNW60VpIw