gotcha.
Off the top of my head:
You should have plenty of free/low cost options in Washington DC, e.g. Smithsonian Air and Space Museum, Holocaust Museum etc.
Mammoth caves in KY is a little out of your way buy should be a solid option. If you do that there's also the Louisville Slugger factory/museum, I don't think it's expensive but I can't remember for certain.
Of course there's the Coca Cola factory in ATL, not sure if that's low cost enough for you...
Great Smokey Mountains National Park
Was just in Louisville slugger factory, I really enjoyed the tour and its pretty cool. Cost is $12 and comes with the free mini bat (I asked the guy for 2 abd he said no problem) it's a really good price.
Smokey Mountain National Park was nice, we drove to Clingmans tower. Was nice but only takes about 2 hours, unless your a hicker. We just drove there and then took a 20 min uphill paved walk to the top of the tower.
Gatlinburg - Pigeon Forge are was amazing. We didn't even do any of the many many attractions there, just walked around and enjoyed the country music bands playing in random places.
There is a new night show called Sablè, was amazing. We got in for free because it was a trial run. They need done perfecting but the idea of the show was great.
