I don't know if you are still playing on Hard, oceanskie? I had a similar problem in my Hard game but I just managed to make it through to the end, with about 200,000 left. In fact I didn't have enough money to complete all the sidequests.
For future reference, upgrade Trading skill to 100% sell value before selling any items. Keep them in your inventory until then. Otherwise you are throwing money away.
I haven't found any way to make money in this game other than by doing quests. But there did come a point for me where the quests were costing me more in new troops than I was getting in reward, so I totally understand the problem.
It won't help you at this late stage, but I can also highly recommend Phantom spell level 3 as a troop saver - creates a 43% size phantom stack that you can use as cannon fodder.
