When planning an engagement party, find a unique place that fits you both. Don't think big venues and catering halls. Parks, parent's homes, favorite restaurants and even the beach would be great locations and can keep you within budget.
Parks/Beaches- FREE(usually) and you can bring your own catering for the event. Plan it during a nice time of year. In Florida, the winter would be the best!
Parent's home- You need to keep your guest list in check, but gives a great family feel. Guests can come and go between certain hours.
Favorite Restaurant- You can rent out your favorite place and share it with your close friends and family. You can also look into Family style restaurants which will offer greater cost savings. Have a Sunday Brunch to save even more.
Save your budget for the wedding..Enjoy!