It's sickening to hear of a 90-year-old woman living alone in a single-family house when she has several adult children fully capable of caring for her.But the first two are the harder issue.

I get about 2 clients/week who want to work with a woman who is knowledgeable, answers the phone and returns calls. 

I negotiated a discounted rental rate on a 24 month lease back in February with a single woman and her dog because she would be the perfect tenant....

So, I rented to a woman who had welfare (which on it's own wasn't the issue and can't be discriminated against in CA), but who also had bad credit.  

Plus, it makes it easier to say no to the ones you like - but should say no to.I feel for that single working woman - I was one, too.  

If they work with you, great, if they have any delay in replying, it ain't happening.So a woman starts looking at the house, and instantly comments "well the house will be jet washed, won't it?"

It's not fair and you'll have an argument on your hands.Noise - tell them they are expected to listen to music and movies and TV or whatever - with headphones.They must have their own phone.Laundry - have laundry rules if you have laundry facilities.Advertise for commuters, if you have a market for that - people who need a place to rent during the week for their job, but have a home they go to on weekends.Advertise for med or law students  - they are quiet and just want a quiet room where they can study.Another good roommate option is a fireman/woman.  

The woman stayed there for three more years and paid rent on time. 

What is so bad about the woman in her 40's? 

She has a small 2 bedroom condo, and she rents out her spare bedroom that she furnished with a Murphy bed, and advertises to commuters.When I was managing an apartment building with mostly tiny studios, I had a woman come and look at them who actually flies back and forth on weekends to a ranch she and her husband live in in Arizona, and she works in Silicon Valley during the week.