I just don't want blight and undesirable things going on next door.So, on the one hand, I feel badly for the investors, but on the other hand, there's a part of me that says "serves them right" because of my experience.Sorry for the long post; I have no potato. :)

I live in the basement unit of a house and I rent out the upstairs to skinny young adults and if you heard the stomping around that I hear you would be convinced they are all 300+ pounds upstairs. 

That will weed out the vast majority of the unqualified and undesirable.

I'd tell them to pound sand, personally.

This also makes a older homes undesirable for the average home home buyer/renter.These are my opinions but hope they help to explain why I am still intrested in the SF area as an investment.

That's why for me California for me seems so undesirable for buy/hold investors (besides the fact that prices are way too high to cash flow unless its recession time 2008-2012)It kills me to hear how long it takes to evict someone in California.  

Said it was just him and a seven pound dog and seemed like he might make a good tenant.  

This chart says a 75 gallon aquarium weighs 850 pounds when it's full:http://freshaquarium.about.com/od/aquariumsandstan...So, I'd argue that the weight alone, could result in extensive and expensive damage to your floors/flooring. 

The tenant had been complaining about a fear a branch from the tree might fall on her 5 pound dog. 

I rent where animals are allowed, and I got a dog that is under 25 pounds, which are accepted everywhere that allows pets - especially so nobody knows she's a service animal.Because my dog is my service animal, though, I don't have to pay the pet deposit.