Here is the website for Cheval's CDD. It may give you some insight to the fee structure. It looks like they are installing reclaimed water and some other improvements.
While CDD's are deterrents it really is just another name for Non-Ad Valorem Assessments or Homeowners Fees by another name. There are also special taxing districts in Valrico and Brandon set-up specifically so the Homeowners Association dues are collected as tax assessments. The improvements of your community will be paid for by the members. So if its not annually as a CDD - it could be whenever the improvement is needed and tact on as a special assessment.