I ran into this scenario often:

1. Having about 2000 in the bank
2. Check the ecenomic newspapers and found that I have a surplus of more than 700 bucks.
3. Went out shopping (not a lot, perhaps 1000).
4. Postman came (without ringing twice) and brought a letter informed me I had a bounce check.
5. Have more florins in the bank now.

Scratching my head: what gives?

I found out that:
1. The economic section of the newspapers is not always correct. It only take into account the costs of paying salary and the potential income, and not counting new buildings.

2. The bank pays salary first, then pay the buildings and train troops (not sure which is first, or go province to province).

3. Then tax is added back to the total.

So, it turns out that I have salary of 1300, left me 700. I was trying to build a keep (1000 bucks), so I couldn't build it. I still have 700 bucks, but the check bounced all the same. And my income is added into it and I have more than the original 2000.

Long story short: build up the economy first to get off the 4000 level before trying to buy expensive stuffs.

Annie