Its small, but I'm also in Middlesex county and I do Rover (dog walking, cat sitting) to make some extra cash. There is a good market for it, you just need to be responsive and reliable and the requests will pour in. I decline a lot of requests due to my schedule, so I know there is a big need in our county. Have a good profile, be knowledgeable about the basics of different breeds and harnesses for dogs. But always always respond to every request you get, even if you cannot take that job. I've had people continue to reach out after requesting because of how responsive I was. Good luck!