When your buying a new guitar online ask the seller has there ever been any work done on the guitar. Ask the seller is the neck in good shape and straight.
Are the tuning pegs in good shape and not loose.

If you're buying an electric guitar are all the electronics on it working properly.

Find out the year it was made and how many owners it has had. Ask as many questions as possible to make sure you're getting a good guitar for your money.

Because you are not there in person so you need the seller to tell you more about the history of the guitar.

One last thing make sure they have return policy this may come handy if you're not happy with your purchase. Good Luck and keep jamming! ♫