Both are 55+ mobile home park communities where you do indeed own the land. Each community has their own set of rules, regulations, pet restrictions etc. You can find details at each of their web sites:
Most of the roads in Holiday Park are meandering ways and the roads in the back of the park feature some big oaks with Spanish moss. The roads in Palm Bay Colony are mostly straight cut.
Holiday Park has HOA fees ($2097/year - roughly $175/month) paid thru the property taxes. Check with your tax professional to see if there is an advantage to that come April 15. The HOA includes basic cable, lawn cutting, use of 2 pools (one heated), clubhouse; laundry, media room, and shuffleboard. The entire park is gated with a 24 hour manned guard at the gate.
Palm Bay Colony has no required HOA fees, however if you wish to use the clubhouse, pool or any of the social activities, to must join. If the unit that you purchase already has a membership, then you are in, if not you'll have to pay a membership fee and pay the monthly fees. There are no gates at any of the entrances. You maintain your own grass.
All of the homes in Palm Bay Colony are double wides & mostly newer than Holiday Park, and the prices are therefore a tad bit higher. You can still get a good valued single or double wide at Holiday Park.
The best thing to do is visit them both to see which appeals to you. I'll gladly take you around.