As appealing as sailing the boat south sounds, I wouldn't do it personally. Any boat that has been unused for several years, and questionable maintenance for the last few years of its use cannot be counted on for any length of voyage. You will probably need a few weeks just to get ready for a day sail.
I say questionable maintenance because there was mention of dementia. I looked at a boat a couple of years ago listed by the daughter of the owner. When I got there the daughter informed me her father had some dementia but wanted to be there to show the boat. There were some things that just weren't right that he had worked on, mostly wiring and plumbing. All things that could easily be corrected with a bit of time but I passed on that boat anyway.
If you can take a bit of time, it may be wiser to move the boat yourself. I realize COVID complicates things and the boat is a wide load. There are companies that specialize in obtaining permits for oversize loads. Here is an example:
We help you get the oversize load, overlength, wide load, and overweight truck permits quickly, affordably and without the hassle. Secure your DOT truck oversize permit online in all 50 states and Canada.
www.permitcompany.com
You could call or email and see if that could work for you. It would probably save you a couple thousand to move it yourself even renting a truck. Heck, you could probably buy a trailer and still come out ahead then sell it when you launch the boat. A DIY move will take a lot more effort on your part but that is usually what it takes to save money.