I'm actually going through much the same as you right now so might be able to help a little. You've gotten some good advice thusfar and the first place you need to start is your food service plan review. You'll have to draw out your truck/trailer with all the equipment, windows, doors, etc. and make sure everything is labeled with measurements. They'll want to know what your plans for sinks, coolers, cooking surfaces, water storage, waste, hot water, etc. You'll also need an approved place to get fresh water and dispose of your waste water. Some restaurants will let you pay to do it there but you'll likely need to find a "commissary" or rental kitchen with said facilities. You'll have to send in a copy of their water bill or go through the motions of going to a government office and having them look up, verify, then sign off on the paperwork so you can then submit to DBPR. Water bill is so much easier...
Send that in with the money required and they'll take a look and let you know what you need to do, if anything. Next you'll do your buildout and make sure everything is at least what you submitted. Sure there are going to be some changes along the way but it needs to be pretty close-especially with fresh water, hot water and waste water. Once you get close to being finished go ahead and fill out the paperwork for the license. You'll HAVE to have the site review first then you'll fill out the license info, get the next check ready then send off for that. They'll usually then have a local inspector call you to setup a time to come and see things.
When they come be sure you have hand soap, paper towels, sanitizer (for pot sink but hand would be great too), sanitizer test paper (litmus paper), pot soap, etc. Have proper cleaning gear, sanitizer buckets, proper storage procedures, etc. ready to rock.
Now here is where the local rules take their separate runs. Once you pass you'll need to be able to sell food in your city/county. You will need to get your business tax receipts for your county and also your city. If you want to sell in several be prepared to repeat the process for any jurisdiction...The county stuff is basically so they know their getting their cut. The city stuff is to make sure you have permission to remain mobile (think ice cream truck), stationary (think a corner lot somewhere) or events. Or all three. Here, if you keep moving and stop only to serve a line, things go pretty easily. If you want to park somewhere they get into zoning, owner approval, etc. Events are a little different but you have to have your tax receipts either way.
Now the last little bit changes from city to city and some make it easier than others. Even some of the people within any departments have no idea what to tell you or who you need to talk to but rest assured someone will catchup to you and let you know if you're doing something wrong. Basically it boils down to the departments who regulate what you do, make sure you do it safely, have the tax info ironed out for the jurisdiction then make sure the cities where you plan on working are ok with what you want to do and get their tax love on top.
Hopefully that helps!!!