There was a interesting thread recently saying that maintenance of army units was based on what land buildings were built in the regions in which regiments were recruited. If I understood the point right, this meant that if you raised a regiment in 1399 in a region without any land building, it would cost you maybe 0.4 ducats per month in maintenance then, but if 50 years later you built a load of land tech buildings in that region, armouries ect, the maintenance would reduce then to maybe 0.2 per month even though the regiment had been raised earlier.
(Looking at my game at the moment, this looks right as I can compare my Essex Demi Cannon regiment at 0.31 ducats per month to my Romagna demi Cannon regiment at 0.39 per month. Essex has an armoury, Romagna doesn't).
Does anyone know if the same rule holds true for naval maintenance?
(I suspect it does, as looking at my frigates, the maintenance varies between 0.08 & 0.05, but I can't tell where they were built now).
It's a lot easier to just build ships in half a dozen regions, so if the same rule does applies, then I'm urgently expaning my naval building line. Regiments I tend to build near where I want them in action, but ship building is concentrated.
In fact, if this rule is true for the ship maintenance, a good move at game start, for anyone doing a WC/colonisation game & needing a massive navy, would be to designate certain regions as ship building regions, build just those up to level 6 in the naval buidling line, & concentrate all ship production there.