I have three solar tubes and 2 solar attic fans...all installed by The Solar Guys. Great tubes and great guys....they're in and out, clean up any debris that might fall (very little mess with installation, really) and the light that floods in from the tubes is amazing.
If you're in Sumter County, you now have to get a permit. Solar Guys get it for you...the county fee is the same for one install or as many as you want or can afford....
I payed around $400 or so it seems, for each, but I'm not positive. If you give either company a call and ask for the price, they will gladly give you a quote.