Your home is your castle, and that includes the property that you own around it. The boundaries of your property are important because they determine where you can do things you want and where your neighbors are free to do what they want.
One way that you can ensure the boundary between the properties is respected is to put up a fence, but you can't just do this in any manner you want. There are specific requirements that are present for building a fence in Florida. You have to know the state laws, as well as the local codes before you have the fence constructed.
You don't have to have your neighbor's consent to build a fence, but you will incur the full cost of the fence unless you have an agreement for them to pay some of the expense. If you choose to do this, you must do this in writing so that you have a legal backing if something happens, and the neighbor doesn't repay their share.
Before you build a fence, you must ensure that it won't be construed as a "spite fence," which is any fence that is put up only to be a nuisance for the neighbor. You can't put a fence out of malice. Your reasoning must be to stop vandalism on the property or to stop trespassers.
Taking legal action regarding a fence should be a last resort, but don't waste time getting the case moving forward when it is necessary. The sooner you get the process started, the sooner you might have a resolution that sets the matter to rest.