One off deep clean of elderly lady's home

My MiL has been struggling to clean her house due to mobility issues and it has become very dirty. She has a cat so pet hair everywhere, and she is a heavy smoker so the whole place is nicotine stained and smelly. She is currently in hospital so it would be nice if we could get it all really thoroughly cleaned by the time she is discharged (don't know when this will be but hopefully soon). No driveway but street parking available at the front of the property. It's a house on three levels with two staircases, and there is a fair bit of clutter which we can help with sorting through.