I bought a property at a tax sale mobile home that was on property was in bad shape so I tore it down so impact fee was already paid for just was wondering how long I had to put another mobile home back before had toanother pay impact fee in the state of Florida in polk county sorry didn't explain myself well in first question I heard you had 5 years

Answer seems to be 5 years:

"Q: Do I have to pay an impact fee if I am replacing an existing residence?

A: No. The replacement of a residence (dwelling unit) with a new residence is not required to pay an impact fee, provided the residential unit is replaced within five years of its removal or demolition. This provision would apply to the replacement of mobile home units within a mobile home park or on private property."

Here is the link. (in the FAQ section)