There are a lot of resources and most give general data. For specific data you will need to have access to the main systems such as the San Antonio Board of Realtors MLS or have someone such as myself gather the specific information for you and share it.
As an investor I look at the very data you are seeking so I'd be happy to discuss this with you.
Please call me at 210-232-2310 to discuss.
Broker Associate / REALTOR
Keller Williams Realty