How To: Cheat Engine for FarmVille - The Definitive Guide

one thing it says you have to be log in as a administrator when installing this program

Amazing.. but sorry, it doesn't work for me..

many many many addresses drop (or increase) when I buy something, there's no way I can discern which is the one I need to change.. Please advise

Best way: trial and error. This is not a foolproof way of using Cheat Engine, but an overview to help get you used to playing around with it. Sometimes it takes a little finagling and persistence.

A lot of times, it won't save. Sometimes, yes. But more often, no. That's how it is with most hacks with cheat engine.