My 99-year-old mother has lived with my husband and me for 7 years now. I retired at age 65 so I could take care of her since her Alzheimer's had reached the point she could no longer be left alone. I deduct $300 per month from her checking account to cover her expenses--food, diapers, clothes, piddle pads on bed, Christmas gifts, etc. Am I allowed to charge her 1/3rd of our home owner's insurance, electric and water bill, property taxes, xfinity and cable television etc. since our home is now her home, too. (She sold her house when she moved in with us.)
My Mom lives in a house that we own. I print out a detailed, itemized invoice that shows things like utilities, prop taxes, rental insurance, maintenance (like yard services), cable, a small food cost contribution, etc. I recalc this invoice at the beginning of every year and the invoice doesn't change unless there's some bigger unexpected cost that is hers to cover. These rules can vary by state so it is best to talk to a professional who practices in your home state.