Quote from @Justin Smoker: @Ashley G. you seem to have a lot of good practical advice based on experience.

The owner was a smoker and the inside of the property was ruined.

All of my major headaches have come from smokers, HUD or not.

Non-smokers only for me now.           

Smokers are not a protected class.  

That is why smokers create beliefs to justify their behavior, such as "I will quit in a year" or "you are going to die anyways, might as well have fun" or "I know someone who lived to be 90 and smoked a pack every day".

A lady puts down that she's not a smoker on her application.

I have 7 section 8 tenants now and have allowed the program in my units for about 10 years.Every tenant I've had drama and/or damage and/or the occasional eviction has been a smoker.  

Non smoking tenants (smokers often break the rules and sneak a smoke inside) no candles and knowledge of electrical appliances throughout the house hugely diminishes risk.