Boston Housing Police (BHA) used to conduct their own tests (not sure if they still do). Somerville Housing Police is operated through the Somerville Housing Authority but doesn't hire too often. Chelsea Housing Police is now run through Chelsea PD.
Most other cities and towns that need police coverage for housing, have an Officer or two assigned as "Housing Police" but they are regular patrol Officers that are assigned to the housing areas but can leave as needed - they are not limited to just the housing. they are Town Police Officers. They often have a regular marked cruiser with "Housing Police" added somewhere on it... It wouldn't be shocking to see a "Housing Police" cruiser responding to a call at the local Mall. Basically the local housing authority funds the positions for the Police Dept. In these cases, hiring is done through the PD as normally conducted.
First of all, get good & liquored up the night before the test. Take the test and score reasonably well so that you will NOT be in the top 10% of the list. The top 10% seem to score well on every test they take so they must be reasonably intelligent, and would not take the job if offered.
If they do accept employment, they see how the place is run like a Chinese fire drill, and bolt for other departments ASAP. Not that there is anything wrong with Chinese fire drills. I just hope I have not offended any Chinese firemen who may be members of this board.
Housing Police departments are sometimes mandated by the courts to be in existance. (Boston) The deal is, it's a good job, decent pay with lots of experience which will help you later on in your LE career if you make it out of here alive or sane.
The relationship with other city Police Officers is what you make of it. I tend to bring the cops in my district flowers and chocolates. On occasion, I have been known to give them some Victoria Secrets nightys, but keep that under your hat. They in turn provide much needed back-up for when the s#it hits the fan. It's a rocky relationship sometimes but the marriage counselor says if we keep to our respective job roles, we'll stay wedded together forever. Hope this helps. HC