I too can see many uses for a service dog: picking things up, light switches, etc etc. The best thing would be to contact the service dog group in your area (I'm not 100 percent sure, but it might be PAWS where you are) and talk with them... they can help you with whether or not a dog would be appropriate, what size dog, timing, etc.
I just did a quick Yahoo search and it looks like Florida has at least 3 groups training service dogs. I would inquire to all three, explain your circumstances, and then see which seems like the best fit.
Good luck in your search!