My understanding is that eve structures are essentially nothing but immovable ships with additional functionality enabled by adding ‘service modules’ and some hackery in the backend to allow many players to be docked at once.
Short of accelerating or warping, pretty much anything one can do in a ship, one should be able to do in a structure when one has taken control.
However, this seems to be completely broken with regard to trade skills.
For example, put yourself in a freighter alone in space…click on the market tab, select some item to buy, click buy and use your remote buy skills to buy something 5-10 jumps away in some npc station somewhere in the same region. Works fine. Done all the time in every ship from shuttle to almost anything.
It even worked in old POS’s and control towers.
Now do that in a structure. It refuses. It says the market service module needs to be installed…despite the fact that one isn’t placing a local buy order or doing anything that require a local market. Bug.
However, I think CCP has done this on purpose to incentive structure owners to buy market service modules. Except, that market service modules are known to make structure much bigger targets. There really isn’t a good reason for this behavior.