What a coincidence that I was just started looking into MIT racecar.

To reduce the cost I did what the Taiwanese group did — used a cheaper LIDAR (RPLidar). Also used a cheaper onboard computer — Odroid. RPLidar is designed to work at 10Hz max (I used an older version), however mine worked at 13 Hz. This is enough for localization and obstacle detection when the car is moving at 2 m/s (which is pretty quick for an indoor environment).

I am not sure what you meant about the static map building part. If you mean to say Lidar + IMU + encoder is sufficient to build a static map then yes. Infact mine worked fine without the IMU as well. The VESC gives pretty good odometry data.