It depends on what the issue is, and also your skill level with doing repairs around your home. If you notice a leak coming from the body of the faucet, then it may have to be replaced or rebuilt. Sure, you can pay a pro, but sometimes all it takes is a little online searching to see how to take it apart and replace some worn components.
That being said, some issues are a lot bigger than replacing a simple rubber seal. Cracked or damaged components may lead to more of a problem than you want to deal with. If you aren’t comfortable with replacing a faucet, then it’s always a safe bet to contact a professional plumber.