You can go to the Lake County Property Appraiser website
Click on Property Search; enter your address, Under the Alternate Key Number click on the number and the property information will open up. If you look under the Millage Group and City:
A number means you are in Unincorporated Lake County (not City limits), or maybe even another City: a GR is for Groveland, MI, Minneola, etc. Remember although you may have a Clermont address that does not mean you are in the City limits.