How many reviews should I have before raising my rates? How often should I raise my rates and by what dollar increment?

Once you are fully booked on a consistent basis (or even overbooked and have to turn away work) that's usually when you know it's time. Some sitters go up by $2-3 each jump, I personally did $5 and waited to see if I was still being requested. If I was still fully booked after a month I went up another $5. If I raised too high and went more than a week without any new requests I went back to the most recent price. Every market is different, so you have to find the sweet spot for your business and area. If you are feeling overworked and underpaid then definitely raise your prices! You're not working to get taken advantage of, after all.