They won't typically be licensed but they are better than GC's half the time and definitely cheaper.

I've been thinking about investing around 50-60k for a cheaper house and just renting it out to pay off the mortgage.

As the buyer does not hold title, eviction is the remedy which is usually faster and cheaper than foreclosure.This is a very general overview and not legal advice.  

I was wondering if I should go with the cheaper house hack and live in a single family unit fix it up then rent it out and buy another and so on and so on.

I could either get it on $40k per year now in a cheaper market or sit on the sidelines for another 3 years before I get in another good rental SFH in San Diego which offers equity, cash-flow and strong rent growth opportunity

These are my standards with every home I buy/sell.The best way to minimize you risk is to buy more expensive properties, that may have lower returns (on paper) than the cheaper homes.$800 + rents seem to have less issues.

In my opinion it is cheaper for you to list your properties through a broker that offers Flat Fee MLS listings services.

This will give you around $200 positive cash flow. ( P of PITI is your profit also...)I bought all my properties build after Year 2000 to keep repair low.Try to self manage in beginning and use property manager after 4-5 properties to get cheaper rate.

Engineered hw is easier to install and it is cheaper, but would the buyer ask about it or can we put it as "hardwood floor" to the MLS ad?

You betcha it is.Because your financing will be so much cheaper (and higher LTV), you can actually offer the seller a little bit more for the house to secure the deal, and still net the same or more at the end of the day. 85% LTV instead of 70% should let you keep a little more liquid to do the reno, to boot.