BTW, I want to add one more point:
- After buying, it will be safer to withdraw small amount of coins to test withdrawal on that exchange for the coin you just bought.
Depends on how small the withdrawal is. Most exchanges have a minimum and you can't withdraw below that minimum.
Also you will be paying double fees for 2 withdrawals. For example the withdrawal fee is 0.0005 BTC on Binance - more than $5. It is not exactly cheap if you are not dealing with a lot of money.
Their withdrawal limit is 0.002 BTC - more than $20. If it is a small amount the user might not be able to respect these limits to make two withdrawals.