Sheltering in an abandoned structure

So you've bugged out.  You've gone some distance and you are planning to stay at a new location for some time.  Maybe a few days, maybe a week, maybe forever.

I've been thinking about some of the things you might want to do, and things you might not want to do.

Shut everything off

If there is a chance that services might come on (water, electricity, gas) you might want to give some thought to securing those systems.  Turn off the water main, shut down all the individual breakers as well as the main and if you can, shut down the power at the main switch outside.  Shut off the gas main as well.

If the services were to come back on you wouldn't be caught off guard by water blasting out of a ruptured pipe or gas suddenly flowing from an open appliance valve. 

Scope things out

You will obviously do some sort of recon of the site before you occupy it.  But once you are inside, take some time to do a complete sweep.  Go room to room, take stock of the state of the the structure, any supplies or resources that are present, and any remains.  You're going to want to remove anything hazardous if it's safe to do so, like dead bodies.

You want to know the location as well as possible so that in the event of a conflict with others you have home court advantage if at all possible. 

Be prepared to leave

If someone else comes along, a potentially stronger force, be prepared to abandon the site and move on.  Everything in this sort of situation is a resource management issue.  Is the fight you may have to put up to keep a place worth the resources the place provides?

Have an evacuation plan.  You had a bug out plan (we hope) that got you out of your home and this far, make sure you have a plan to bug out from here.  This might require more planning and recon, but life in a world that isn't governed by the rule of law and the 24 hour news cycle is all about planning and recon.

Have another spot in mind

If you can, have another location in mind to jump to.  This sort of goes along with being prepared to leave and having an evacuation plan, but it's more also.  You will have done your local recon as part of setting up where you are.  Part of that will also be picking other spots to jump to.  You should know those locations, perhaps have supply caches near them, but not be set up there.  They are potential fall back sites so you should have already shut everything off and scoped the place out.

If you have to fall back to one of these sites a quick recon will tell you if it's safe, then you can move in.  Probably not for long though, since you had to abandon your primary site to some other group.  They will begin to occupy and scout the area, so you will probably be moving on and beginning this cycle all over again.

It might not be an enemy

You may have had to abandon your primary site for reasons other than hostile people.  Maybe a tree came through the roof during a storm, or it was flooded by torrential rains.  Having an alternate site to fall back to is just as helpful under these situations as well.

Conclusion
Do you have any additional advice or pointers?  Let me know in the comments.