Just starting and not clear about housesitting or drop in visits for more than 1 pet?

Having worked for other services in the past, in addition to running my own business, generally when I house sit, dog walk or for drop ins, if there is more than one pet there is an additional fee. I have already discounted my rates heavily as it is from what I normally would charge, and I am fortunate to have booked one, maybe two clients my first week. But both clients have an extra pet, a cat and a dog, even though my rate is for one, I'm being asked to care for both, walk, feed, water. I need a bit more clarity going forward. Do I bump up my rates, or is there an option for a second pet? (much like holiday rate bumps it up by $5).

I'm willing to be more flexible to build up client base and reviews, but need more clarity from Rover, to help me decide how I want to move forward.

Thanks in advance!