We have not had it appraised but we did look it up on our county appraisal district website and it about $100,000.

SFRs in the suburbs are for growing families who want to be in certain school districts--these properties will have high property taxes and be at the more expensive end of the spectrum, but you can find fixer uppers and sell them at a good price after rehab if you are patient and look deep--try auction sites like Auction.com, Williams & Williams, Xome, Hubzu.

North Collinwood is turning into a nice arts district.

Even if it is only currently a legal two family, if it is located in the right zoning district, the "use" of a four unit building may be allowed and it could be an easy legal process to do the conversion. 

It didn't cost much at all compared to the above.A little bit off topic, but Westwood is interesting as well because they are trying to convert Morrison road, the road that cuts diagonally through the neighborhood into a cultural district.

If school district is not a concern anymore, are there any reasons why I should not invest in Hayward, CA if I am looking at it as a 5 year investment?

I acquired my first and only property in Jan 2017 - triplex in the Mission district in San Francisco, CA and am living in one unit.

Additionally, the property has to be in the same school district as the school you work in

You are in a non-historic district.

There are some great opportunities for flips in some neighborhoods, its already happening.One location I like for flipping is University District if you can get in cheap enough and BagleyBala