A client wanted to book her dog from xxxx to xxxx but wants to get the dog during the day and bring her back to me at night. Are we allowed to do this? In my understanding, the dog should be with me on the dates booked and should not leave my premises?

You definitely can customize the booking according to your agreement with the owner. It's stated as the recommended guidelines are up to 24 hours and depending on the situation of what's best for both parties and the dog, some different arrangement may be agreed upon. The dog may experience more separation anxiety as a result.

I'd recommend you can use the message section to document that agreement (something to the effect that during the dates from/to, the owner plans to pick up the pet around XX:XX AM and will return the dog to your care around XX:XX PM daily) https://support.rover.com/hc/en-us/ar...

I have asked a sitter for a custom arrangement like that. She used enhanced day care rates (the sitter can edit the rate for each service when a booking request is sent). I dropped my dog off around 11 am, and she returned him to my hotel around 930pm each night. Worked well on my vacation as an obsessed dog mom. Depending on need, be prepared to pay a fair amount extra--but for some people, it's worth it, especially from a quality sitter.

As a sitter myself, no one has require an extra service like that, but I would be open to most things.

It is opposite of daycare. The customer wants night care only. I would use the daycare designation and document the hours of care in Rover's system.