I couldnt get RPGMakerEditor to work for this game.
So here\s the alternative way to do it, in any game.
1. Get Cheatengine.
2. Get some money.
3. Start engine, connect to game.exe, then do a first search with "unknown variable", then walk around a bit, go to different locations open menues etc, then for next search do "unchanged value". you should now only have static values left. If you have a lot of results in "0", then just do a "higher than" search with 0.
4. Go to a store, buy something, check for decreased value, sell something, check for increased, repeat until you find the one that connects to the monetary value, in the end you should only have 3-4 left and be able to guess witch one is the right one.
Increase that value, go into game, check gold balance, looks good, then save.