Wish I could do more!
Hello, I'm the one that recommended you this site on Y!A. I would help you myself if I could, but I'm on the whole other side of the country.
I really hope you can find an experienced person close enough and willing to help you out.
Now that you suspect it's a boa you could probably move this to that section for some better advice. There's also an adoption section for animals in need of homes, but I'm not entirely sure if it's fitting to post a "wild" one for capture there instead of a pet for pick-up....
To get your message out more, there's a website that deals primarily with boas called Redtailboa.net
I'm not that familiar with it, but it's suposed to be pretty good. They have a "Help Me" section and also a "Rescue" section.
Then of course there's always Craigslist, though if boas are illegal in your area then you probably don't want to be posting about it. I'm not familiar with your state's laws, but it doesn't seem to be a "Reptile of Concern" and I don't
think they're banned, especially since this one's under 8 feet. I'm no good at following along on which laws are which, but if they're okay to own without a permit then it should make your search much easier than if it was really a burm.
Craigslist has a lot of "Found animal" and "Free to good home" ads. They have a section for the Tampa Bay area I'm pretty sure and under "Community" there's a section for pets. Perhaps you can put out a message saying you're looking for contact info for a local reptile rescue, or you can send out the same message you are now - that you need a boa removed from your house. Try to make sure they have experience with boas or at least larger snakes if you can and that they can care for it. I'm not really sure what goes into that kind of rehabilitation, but I'm pretty sure it'll need to be treated for parasites at least. Hopefully it's healthy.
I already checked your area for some local reptile rescues, you're right about a lot of those numbers being expired, their websites are too....I've found several trappers, but I'm under the impression that they euthanize them afterwards.
If it's any bit reassuring at all, know that I
highly doubt it even could eat your neighbor's dog. Honestly I don't think it's a threat to you, your family, or pets. I'm sure they're nocturnal like most snakes and I know they prefer to just hide. Boas are normally docile and I don't think he'd go out of his way to bother anyone if left alone.
Still best to play it safe, I think that you should just give your neighbor a warning to keep an eye on her dog the dog until this clears up. Make sure it doesn't get under your house or near the area where you saw it. It's unlikely, but there's no need to tempt fate.
Really sorry I couldn't help more. Best of luck to you, I've got my fingers crossed! Hopefully someone turns up and it goes to a good home!
So thank you for keeping me posted, I wish I saw it sooner!