It truly depends on the rehab amount (if any), rent rates, the market, and the population/demographics of the area.Now when using the 70% Rule, a rule that many investors use, adhering to this rule will most likely, cushion the deal providing that protection first, then profit.Now there are strategies that may omit the 70% rule.Here is an example of when a 70% rule becomes obsolete: A person comes to me and says he owns a home with a $100K note on it.

It appears some of the techniques he talks about in the book are obsolete since the housing bubble burst in 2008/09 (putting only 10%, and even in some cases NO money down).

There are so many alternatives to just crying about how its not fair that the easiest option is becoming obsolete.

You also have inherited properties, obsolete properties, under rented properties and more.

There is a lot of obsolete retail properties in our future.  

Sometimes you just need to move a wall or take a wall out, to make it less functionally obsolete, but you can still keep the character. 

Just as an example families combined with two wage earners made a lot of urban multis obsolete...changing use to condos drove appreciation.

Yea replacing obsolete windows is a pretty good bang for your buck.......Unless work is needed in the kitchen and/or bath.

With that said, some courses or degrees may be perceived as obsolete (not to name any).

Agents are more or less consultants this day and age, but who knows if technology will continue to progress to a point of making agents obsolete, or at least changing their roles even more.