I will be provided a bedroom and meals; I need to be there overnight as a companion in case she gets up and needs help with toileting (she may have problems with clean-up); I will cook her meals, clean house, laundry, etc... I will stay there M-F; they will have another person come in weekends. Plus, a respite person ( possible family member) on call or for our personal needs. I do see this as a live-in in sorts, but not in exchange for room/board. How do I charge?? I am new to THIS type of situation. Thank you for your advice!!
https://www.irs.gov/businesses/small-businesses-self-employed/family-caregivers-and-self-employment-tax
You do need to have a written agreement that spells out your EXACT duties and EXACT hours. The 90 y.o. is semi-independent, but that will change. The senior WILL need more and more help. Will you be expected to take on more duties? If so, the pay must go up as well.
Make sure you have an exit plan in case things don't work out. You don't want to be fired and expected to leave the next day.
As far as pay, I think it depends on the area and the cost of living and rent. Where I live, I heard of a few arrangements where the person comes during the day ONLY, no overnight, gets an average of $2,000 a month.
In your case, you're on call and expect to work over night, so you should get more. Boarding and food should not be deducted because that's required to do your job. How can you help the elder if you don't live there? If you have a regular job, you don't pay rent for your desk or office. Same logic applies here.
I have an acquaintance that works as an overnight sitter. He comes over to stay with an elder overnight. He sleeps there. He gets paid for all the hours that he is there, sleeping or not. Of course, he doesn't pay rent for having a place to sleep. You shouldn't either.
Make sure everything is in writing.