If you get a girl, get her spayed early to prevent a accidental pregnancy, since Bostons can have major issues giving birth. It's common for them to have 2 puppy litters, so getting pick of the litter could mean you get the ONLY puppy or one of the two available. Good choice.
You should make certain about the parent's knees, eyes and nasal issues too. Bad knees, dental issues, eye issues and nasal issues(as well as cleft palate) can crop up.
Dachunds are actually great dogs, you just need to train/raise them like a german shepard or bulldog. They don't know they're mini. They also have major issues with obesity, which for THEM is dangerous because a couple extra pounds can put way too much stress on the spine. We have a lot of great dachund clients and a few annoying ones. None of our clients are barkers, but I know a few people who have mentioned barking dachunds too.
Good luck with the new puppy next year. Make sure you keep the facial folds cleaned with baby wipes.