Building a tri bike for the wife. I have a couple of sets of 650 wheels and some other parts. She has test-ridden a current low-end profile and liked it.
Saw one on ebay recently with a $350 BIN price, though it didn't make reserve. Either that's a high price or they are a niche item.
Other tri -TT frames 48/49 size might be considered, though this is a budget project.