You made a mistake, it would have 2 200 denars.1. Villages aren't changing prices during the trade. Is it intended? Sometimes a village is offering a very high fixed price for some trade good. For example: a village has 100 x fish to sell for 12 each and 1 000 gold in the bank. So, if I will buy all these fishes, it will have 13 000 gold ready to spend.
0.5% inflation a day is HUGE. It's already 1 210% of base price after 500 days (6 ingame years).2. I had this thought about inflation. Wouldn't it be a good idea to add it to the game? It would help in keeping the numbers on a reasonable level and also it would encourage players to make the cash flowing all the time instead of banking it up. I'd suggest around 0.5%/day inflation (to make things transparent, player would just lose 0.5% of his banked gold daily). It's 500 gold lost per 100 000 gold banked per day which seems reasonable. 0.5% may be too high, it depends on how the economy will be balanced in the end.