Translation: I am selling the house to a co worker, and you will get the tax lien paid.

I'm not sure how $20 a month translates to $3000. 

Sure the raw number of 150/month may be the same, but you have to spend an extra 50k to achieve the same raw cash flow in the good school district which alters your ratios.So in the end the C class asset will cashflow better, and the A class will probably appreciate better. 

My wife came to this country and never even bothered to translate and register her diploma and four-year-degree.

Yes, prices are high, cap rates are low, but roughly translated, that indicates very low risk.

Roofs do not require any permits unless you 'alter the diaphragm' meaning replace sheathing.

Feel free to use in your analysis.Capital_Req = (1 - Debt_Perc) * Surplus_CF * 12 / ( Net_Cap_Rate - Debt_Perc * Prin_Int_Perc )E.g. (1 - 90%) * 4000 * 12 / (10% - 90% * 5.75%) ~=100k in Capital requiredA 10% cap rate, owner occupied property at 10% down payment and a 4% 30-year fixed mortgage through a no-PMI portfolio lender (the latter translates to ~5.75% principal+interest percent) gives you ~100k in capital required to generate 4k in monthly cash flow (assuming moving out of the owner occupied after 1 year). 

Don't be angry if you need to repeat yourself or maybe use a translator to get your point across.

Alterations in buildings built before 1978 are generally (if not always) regulated by the EPA:http://www2.epa.gov/lead/renovation-repair-and-pai...If you simply want to know whether the building has lead paint in it you can purchase lead paint test kits at Lowes and Home Depot.You'll also have state specific regulations governing remodeling/renovating activities and licensure.

High rents don't always translate to high landlord profits.