There are a few hotel suggestions in the travel section. There’s a wide range of hotel options in Nashville. Because it’s a holiday weekend, I would suggest booking early. There’s a very large fireworks show in downtown Nashville on the 4th. If you want to see it, staying downtown would make access very easy. If you want to stay away from those crowds, I would recommend Midtown or the West side.
This is an evening for the grown-ups. Get a sitter and enjoy yourselves!
Yes, there is ample parking at Green Door.
Attire is Farm formal—basically, get dressed up but wear shoes that you feel comfortable walking in across gravel and grass for the ceremony. The reception is indoors on solid ground if you want to save your stilettos for the dance floor.