This might create a problem when you want to sell the property. The home inspection looks to see if permits have been pulled for qualifying projects.

Why would anybody install their own mini split system or put in a terrible looking hotel type unit on the side of your house? If any of my neighbors would put in 1 of those hotel units where I can see it, they would be reported, sorry.
Not all mini split systems are taxed or are put on your tax records, you buy 1 from a dealer that classifies it as a dehumidifier, plus you get a federal tax refund.
I bought the better looking mini split that gets installed in your ceiling instead of having that big ugly unit on your wall. Sure it was another $1000 but well worth it to not have to look at the ugly indoor unit every day.
Also, if you do put in a mini split, get a smart thermostat for it and throw away the remote you have to use. I have a unit that is comparable to an ecobee for my mini split unit to have different programming scenarios for heat, cool and time of day

Let me clarify, I will be getting permits, building and electrical, but I had 2 estimates for this work, both were in excess of $5000 to $6000. This unit I am looking at is less than $2000, and allowing $500 for permits and actual inspections, there is a considerable savings. I was looking for the potential gotcha of using the unit as a dehumidifier only. I was told there was a "module" for this type operation, I will be calling Mr. Cool for additional info.

Mr cool mini split.
 

I installed one myself this past winter. My Lani is right around 600 sq ft, so I did go with the 12000 btu, so I could use 120 volt electrical, if you go higher than 12000 BTU, you do have to go 240. Also the 12000 BTU comes with precharged 25 ft cooling lines, and electrical line. Just follow their instructions, and you will be fine. I did buy the brackett that bolts onto the house, it is a very well made brackett, and does have a small level built right onto the brackett, and I also bought their package of covers to cover up lines. The only thing I hired out was electrical, because they do tell you to have a shutoff box next to the unit. I believe all the Mr Cool units heat and cool. I was really impressed by the heating and cooling of the unit. The whole package cost me around $ 2200 dollars.

I would be glad to help you out on the installation, just let me know when you’d be ready.

I just got an email from Costco and they have a Mr. Cool 24K btu mini split on sale for $1999 which is $300 off their normal price. I thought I would pass this info on in case it's a better price.

Looking further into this they also have the 18K btu unit on sale for $1899 and the 12K btu unit for $1449.

@villageTinkerer. Can you provide any update on your project ? I will be following in your footsteps.

Never installed, I tripped over the class 3 enclosure rules. Basically, you CANNOT get the required De-Humidity functionality from any of the companies that carry the DIY (Mr. Cool etc.), they will NOY supply the letter that the local A/C companies have been able to get for the Mitsubishi systems. Ths letter is required for the building permit, etc. So my only option is to pay one of these companies $5000 to $6000 to install the system that I could buy for $2000 and install myself. As for the class 3 rules, for Sumter County these state the room will not be air conditioned, hence the only option is the De-humidifier option.

So - I just checked the VCCDD about something else and saw that only central air is allowed, /and/ no window units are allowed. A mini-split isn't a window unit, but it's also not central air. On the other hand, mini-splits didn't exist when the deeds were written up in my part of The Villages. So do they fall into a grey area where ARC won't forbid them on a lanai? OR will ARC allow them if you ask? Or will they order you to remove them and patch up the hole in your house if someone files a complaint?

My intended usage is to cool / and reduce humidity in my garage. Does a garage install still require the letter for a building permit ? I get the sense it is related to square footage requirements, but frankly, I'm just wading into this pool and have a lot to learn on the ARC do's and don'ts.

No idea on the garage, you need to call the building department.

ARC was NOT the problem, the problem is with the Sumter County building department as you do need a permit for a lanai installation, both electrical and building permits. It is a long story, but feel free to send me a private message and we can discuss over the phone.