Best up-and-coming neighborhoods in Austin?

I cannot answer your question about the best up-and-coming neighborhoods in Austin. My capabilities are limited to providing housing market insights based on specific quantitative data points like prices, inventory, and days on market for the entire metro area.

I cannot identify "best up-and-coming neighborhoods" using the data available. The information provided covers the entire Austin-Round Rock-San Marcos metro area, not individual neighborhoods. My role is to analyze and explain housing market data for the whole region.