Cost is established by the developer or homeowners association. When a developer is in control, maintenance fees may be temporarily subsidized by the developer as a marketing tool while there is sales activity. After the homeowner association takes over, fees may quickly rise to unsubsidized levels. These assessments are passed by the association board of directors. Severe storm damage would be an example where an extra assessment would apply.
Timeshare ownership is an investment in quality vacations.
Purchasers who buy a timeshare strictly for speculative reasons are usually disappointed as the resale market for timeshares does not appreciate as well or as fast as other real estate investments. All factors being equal, a resale from a previous owner or a resale company, will probably cost considerably less than buying direct from the developer. There are instances where buying from a developer may be your only choice. I think you know the answer. The answer can be as individual as each owner but the consensus answer falls into two categories based upon intended use.