[villages07]

Actually, though succinct, it was probably the best answer to your question.

The amenity/water/trash bill .... The only item that could/will vary greatly from month to month is your water usage. The amenity and trash fee are pretty much fixed with perhaps one small increase each year.

Take a closer look at your water usage...potable and non-potable (irrigation) and see which has increased. That will be your first clue where to investigate. If potable, you may have a leaking faucet or toilet. If non potable, either irrigation is running more often or you have a leak.