That's what my next door naighbor did. She was layed off. She had been sitting for a few people on our block, covering both dogs and cats.
Comes in at lest twice a day, morning and evening, feeds per owner, walks, plays, cleans litter box, makes sure that the water is clean. $16.00 a vist.
Now back to work, but still sitting. She is bonded so that people feel safe with her.
Side note: she loves both cats and dogs, and they love her. She has about 30 clients now