Austin, is crazy expensive, but that is mainly true inside of the Central Core of Austin, and other areas west.
The central core of Austin is defined by a "square" roughly defined by everything west of IH-35, East of Mopac, North of HWY 71, and South of US 183.
Most of the homes that are in that "square" are very expensive and tend to be around $400,000 or more.
However, there are some pockets of town that are not expensive and may meet your needs. There are many new construction communities that are being built in the South Eastern Side of town that have price points in the high 100s. There are also some neighborhoods that are older-established neighborhoods that are in the mid 100s.
You may want to look into Pflugerville or Leander. Homes there tend to be more affordable than Austin.
If you'd like more information, I'd be happy to help you.