I would not consider buying redbuds sight-unseen. Redbuds are notorious for having poor form (sharp branching angles that cause the tree to break apart after a few years). The only way I would buy redbuds (except maybe for seedlings that I planed on carefully pruning to establish a good form), is to carefully examine every one for good branching characteristics. Redbuds are pretty but they tend to be poor quality trees if not carefully monitored and pruned.

Premium nurseries (aka expensive) will often have high quality redbuds. If you choose this tree, I would recommend spending the extra money and getting higher quality trees or starting with seedlings and carefully managing their growth for the first 5 to 10 years.

Interesting thoughts, Brandon.

I've got several volunteer seedlings that I've been encouraging for the last few years. I never thought about checking their branching angles. I'll have to take a look at em!

Once you have branches at the level you want, you can use plant tie tape for support below the branches and branch spreaders to increase the branching angles. If caught early enough, branch angle can be changed. Redbuds have weak easily split wood, so increase the angle gradually. Another tool that you might use is pantyhose tied low on the branch (close to the trunk). This would be easier on the branch than string or rope.