It depends upon how the current one is installed. Faucet removal is the first step and if the existing one is a real mess, corroded pipe, bad solder, poor routing etc it can be time-consuming to remove it. I removed mine in a little over 30 minutes but it was pretty easy. The hardest part was getting to the bolts that affixed it to the sink.
Then you have to decide how much plumbing needs to be done. There are several ways to install plumbing securely.
I just replaced my bathroom faucet myself and I talk about it here:
I did get two quotes to replace my sink by a professional plumber. It ranged from $200-$400.
Ultimately, I decided it wasn’t too hard to do. I spent about 2 hours total on the sink. I did a lot of Youtube research first though and I didn’t count that time in the work.
Good luck.