need advice ---what should i do to summerize r.v. in florida

If you have vent covers then keep the vents open. Good air flow will keep the mold down. Houses close to the beach do not have mold issues due to the sea breeze. Just look at their roofs. For bugs. Use a dust like 7 dust for under the RV. Remove all food. Use Combat bait for roaches.

down home has it right. Assuming access to plumbing and sewage, why not leave the grey tank dump valve open (not the black), and route a dehumdifier's drain to the bathtub or a sink (making sure the sink drains to the grey... some bathroom sinks drain to the black tank.) That would take care of the humidity in the rig.

I'd probably leave both A/Cs on a temperature like 80 as described above, if only just to exercise them so the compressors stay active and don't seize.

The black tank, I'd dump, rinse, then pour a gallon or two of RV antifreeze in there. RV antifreeze won't evaporate, so it will keep things in the tank from turning to "stone". I'd also pour RV antifreeze down the sinks and tub as well to keep gases out of the coach area.

Battery, I'd check to make sure you have a three stage RV converter. If a single stage, chuck it and get a better model with Charge Wizard-like functionality, which will trickle charge batteries when near 100% charged. A single stage converter will boil the battery in no time.

Water, I'd disconnect and leave disconnected. That way, if something would spring a leak, you don't have a flood when gone. I'd also drain the tanks and run the pump dry so there is less water that turns to algae while gone.

Refrigerator, up to you. I'd probably fill up the propane tanks and run it on gas while gone (a propane fridge will go through a 20# bottle in about 30 days), which will keep the spiders out of the flue. Cheap insurance, since an insect infestation can get expensive. Just remember that the fridge does use 12 volts, even on propane so it will drain the battery dry in a week or two unless it is being charged somehow (shore power, solar, etc.)

Oh, don't forget to put screens on the furnace, fridge vents, water heater, and other items... otherwise, you might find some hornet nests or mud dauber wasps have made themselves home in there.

On site? Electric? use a home type dehumidifier. Set it in the shower or otherwise plumb drain to outside. Leave one air conditioner on at about 80.
I know it cost electricity.
You're going to have someone check, it anyway, once in a while?

This may sound silly, but it does work. Get some citronella camping candles (2 or 3 of them), open them up and simply put them inside your camper. Do not light them, just let them sit. If you get the camping type that comes in the miniature buckets, those are perfect. Simply open them up and leave one at the front of the camper, one in the middle, and one near the end, and close up shop. The citronella will keep ANY bug from EVER wanting to enter your camper. It works, we use to do this all the time. Also, it works when you're actually camping too. Keeps mosquitoes out. They don't even hang around the outside of your camper. Do not light the candle, just let it sit open.

As spoon59 says have vent covers on a front and back vent so you can leave those vents open - ventilation is a key. Leave the refrig doors ajar. Disconnect the battery. Put screens or covers over openings for the furnace, etc. to keep wasps out.

I would purchase some Defender (for bugs) from Lowes and do the perimeter of the trailer making sure to get all the points touching the ground. Crack the air vents for ventilation. Set out several damp-rid containers (Walmart).

The best solution that I have found for humidity is to allow it to ventilate. I have vent covers in the bedroom skylight in front and bathroom skylight in the back. I leave both of them cracked open about an inch, which allows fresh air to flow through. Before I did this, I would have that damp smell in the camper. Since I started doing this, no more smell.

Bugs are harder. They can sneak into the basement compartments, which are rarely completely sealed from the interior of the RV. I would clean it really well when you are putting it in storage and get rid of any food scents. That will make your RV a less likely target for bugs.

I just keep my trailer plugged in year round (but I leave it in the backyard). Keeping it plugged in keeps the battery charged. If you don't have that option, I might suggest a solar battery trickle charger.

I always make sure to drain my water heater and open my low point drains when I am driving back from the campground to completely drain the water out of the camper. One time I forgot to drain my water heater and got that sulphur smell from bacteria in the water.

Hope this helps!