Tips for Late Game Economy

[Methuselah969]

I've worked up to playing on Prince and I can't seem to keep my economy in the black, right around the Industrial era or sometimes a bit sooner. I just end up constantly losing $$.

My only saving grace is trying to focus on golden ages where I can increase my economy but it doesn't always work out.

I do build as quick as I can, market/bank/stock exchange and try to keep an equal mix of trading posts on city tiles.

It get's so bad late game that I wind up -100 gold every turn. Even if I choose social policies that reduce my maintenance $$

I do tend to keep an army garrisoned in every town and a couple of siege weapons for taking over other civ cities. I know this is where a majority of my costs come in but it's like you can't have a strong army and expect to maintain a strong economy.

I know that in one of the patches they allowed you to delete/sell obsolete buildings but for the life of me I don't know what buildings are considered obsolete. I also have a tendency to build every building available (except some of the military buildings and walls).

Does anyone have any tips on how to shore up a strong economy?