If you are looking to invest in SFH with good schools which would give you decent cash flow and good appreciation, I would suggest to buy slightly outside city limits where the property taxes drops significantly which will help in cash flow. Far west is a good area to explore as well as houses up north which zones to COMAL ISD. Have excellent schools and low tax rates.
If you are looking at duplex, I would look for something in South San Antonio as well. It has a good number of blue collar workforce and very good rental demand.
@Dilsingi Rag The best cashflow is going to be in the worst parts of town, but requires a very hands-on approach and it is WORK. Start looking south of Highway 90 or west of I-10 near downtown