BattleTech has this weird thing where, even if a factory is razed to the ground, for some reason they will rebuild it in the exact same spot, even if that spot keeps getting razed because it's one jump from the DC border. This seems to imply that for some bizarre reason*, spots you can build a factory on are exceedingly rare and it's better to keep using that same spot, even if it's right on the Coordinator's border and everybody knows about it. Otherwise by all logic, the smart option would be to instead rebuild the factory about five jumps further in, and closer to major trade hubs. Also, the only ones who seem to know how to build factories in space are the Taurians, and if they exist in your setting, the Belters.
*I realize that Doylistly, it's the writers not wanting to have to write up new planets and such so they just rebuild the factories in the same spots century after century so that the map never changes much.