Buying my first TT, and I have a few questions

Totally agree with Donn. Dont buy first trailer new because once you get one you will come up with a more refined idea of what you want. Then you'll trade in your new TT and take a huge hit on depreciation.

Also nothing wrong with a rubber roof (I prefer them) and you don't have much choice anyway.
Black tank sprayer is very nice to have but you can stick a wand down the toilet and do a better job. (I have the flusher and still use a wand).