With a vacancy I have costs associated with the turn in addition to lost rent while its vacant.

The fees I charged as a LTR landlord more than made up for additional cleaning expenses.

I do not want spend my W2 income to cover house mortgages, to not have pressure if things like layoffs will happen, so my plan is to buy house in a good neighborhood that may have appreciation and some minimal cash flow after all expenses (management, maintenance and vacation).

Additionally, Beaver Falls is relatively convenient to navigate to the city and other areas, a 15-20 minute drive to the airport, and easy access to 376. 

Build a legal rental unit with kitchen, bathroom, new windows and others, according to the design from Sokol Design-Build GroupDig out the basement and install a new concrete slab, it's a separate addition job and will cost $ 15K - $ 20K.much better than the first one (and yes both are insured and are experts in the field) I may have to GC this project myself to save some money. 

If that is the case with this property you will have to determine if the septic system can handle the additional bedrooms.  

It's wise to take into account market research and any upgrades or additional benefits for the tenant.Determining when to raise the rent is influenced by various factors such as lease renewal dates, local market conditions, tenant satisfaction, and lease agreements.

Will this area see a huge increase in value and rental income?

In these cities, your financial resources will go a long way enabling you to assemble a diverse multifamily portfolio and initiate a steady stream of income.

Since the basement would be used more so for us living in the unit and not rental income, do the same code/zoning requirements apply?