elderly dogs or dogs with special needs
It sounds like a bad idea honestly. It isn’t a dogs fault that they are on medication. Charging more for that seems like some form of discrimination, owners are already out-of-pocket more when buying the medication and vet bills, why place more burden on them? I would worry this would make your boarding requests go down even.
But if you insist, you can always manually add the fee when modifying the booking. I would advise that you disclose the fee in your profile so that owners are aware ahead of time, otherwise it could cause you sitter performance to go down when clients Change their mind about booking once they see the fee.
You didn't specify what kind of medication, whether oral or injections. I am not qualified to give injections, but I am perfectly capable of giving a dog a pill or two or three. I don't consider it a big deal. My own dog is practically blind. He gets multiple eye drops daily.
This question has come up before several times. You might want to read these threads:
I don't add a charge for medication, even shots. To me it is part of the routine care a pet requires. Be sure to follow medication directions carefully and ask questions about what the meds do for the animal. But, if a situation is out of your comfort zone, say so.
You CAN charge extra for any additional services you choose. Since Rover doesn't have that option available, you would need to specifically list this on your profile and then manually add the price to the total price.
The only time time I charged an extra fee for giving oral medication was when I had to chase 4 ducks down to give it to them!