can I contact Pet Sitter before I book a specific time?

Of course you can contact any sitter prior to booking. In fact, Rover encourages you to meet with them to discuss your expectations and see if it is going to be a good fit for you and your pet. Just click on the contact button to set something up.

As a sitter, I will never just accept a new booking with a new client without setting up a Meet & Greet. As a pet owner, you have every right to interview a Rover sitter or walker.