We recently had a tenant that just moved out.  The house has the water heater outside, and so we built a small room around it and put a door.  After the tenant moved out, we noticed beds and various other paraphernalia in there.  Basically there are transients that are living there and preventing this house from being rented.  

Steps I have done so far:

1) deadbolt that door

2) Lock on the outside gate

3) Setup a police patrol by

After the above three are complete are done, my hopes are that it reconciles the problem.  What I fear is retaliation and the house being vandalized. I do not live in the area, but close by.  Would love some ideas of other thing I can do to get these folks out.  They are doing drugs and defecating all over the damn place.  Was not sure if there is a way to have the city remove them or place them in a better place (homeless shelter etc)?  The home is in San Antonio, TX.

Thanks!