Quote from @Brandon Croucier: Fico, LTV, Experience, Make sure no BK's or Foreclosures.Those are great points to consider when evaluating potential borrowers.

You could not change the rent at all, and they could still pay more by a re-evaluation by section 8.

I continue to evaluate deals these providers send me and if something penciled I would definitely consider buying more. 

Since you're in Europe and can't visit the property, you can hire a professional third-party home inspector or a local property manager who offers property evaluation services.

I'm about to buy to 4/3 home that's 2,300 sq ft, built in 1967 and want an experienced real estate investor to evaluate whether it's a good deal.Please comment below if I can pay you for 1 hour of your time to analyze it.I have full photos/video walkthrough, and also have several contractor quotes.

Everyone has to do their own evaluation though. 

But if “by doing” he means investing without first having the knowledge to KNOW the risks, EVALUATE the risks (and potential rewards) and to TAKE ACTION to reduce the risks then the cost of this learn by doing education is probably going to be significantly more expensive than a degree in real estate from MIT, let alone reading the\ree or four texts on your own.  

So, let’s evaluate.  

This strategy requires careful planning, from evaluating potential properties to ensuring that your rehab costs don’t spiral out of control.

You’ll want to understand key metrics like cash-on-cash return and cap rates to evaluate deals properly.For flips, it’s all about finding properties where you can add value through renovations and sell for a profit.