My muse for this post is an unwanted POS that appeared in one of our wormholes. It is gone now, cleansed with fire. The loot fairy was unkind.
Getting access to a Foo corp wormhole is almost as easy as reading our recruiting page. Even simply doing PI in our wormholes (i.e. paying a small amount of tax) is generally enough to get me to chat rather than shoot.
Is it occupied?You should check for a forcefield. This means not only checking inner planets, but also all of the outer planets as well. Have a look at the system information, or even the overview. Make sure you have a dscan that covers every planet. A forcefield means the system is occupied. Any storage array (ship maintenance, corporate, personal or assembly) without a forcefield means it is time to pop a loot pinata. Any POS that is coming online, anchoring or offline is a gank opportunity with a timer. An offline POS with none of the above is (most likely) abandoned.
Be aware that if you move into an occupied system that the locals may be invested in defending. If you are looking for a fight, maybe that's a good thing. If you are looking for that fight, make sure you are ready for it.
Do you have spare scanning ships and pilots?Far too many pilots only have one scanner in a wormhole. This is what alts and other corp members are for. There is no point in having 2B+ of assets in a wormhole that you can not get back to. Pilots will almost always shoot pods in a wormhole, as it will generally take you that much for hostile pilots to return to the field.
Does your POS have defence?A small POS should be treated like a glorified mobile depot. It is disposable.
A preferably large POS should have a desired mix of short and medium weaponry, ECM, neuts and a (initially) balanced resist profile. Others will promote the merits or disadvantages of Deathstar vs Dickstar.
Guns should be scattered and not grouped together. Attacking fleets love it when you group your guns as it makes it much easier to position your fleet.
No fuel means no defence, no access to POS.
No strontium clathrates means no reinforcement timer, and hostiles can grind you down in one sitting.
Will your POS shoot (only) the wrong people?Outside of highsec, your POS generally should shoot neutrals. That is, attack if standing is lower than 0.1. Setting Attack if at war also is a good plan. All the POS guns in the world don't do any good if they don't know they need to shoot.
POS have no idea about pilot standings; they only pay attention to corporate standings. As far as I know (and partially tested), POS are aware of inherited corporation standings if you set an alliance to blue.