I don't drink, I don't smoke or do drugs, have never been arrested or in trouble with the law, and I am currently working on my Ph.D. in Chemistry at a top University.

The difference between John and myself are a bit stark...You see I am a strict teacher, ex Marine, taught Chemistry and Public Speaking in HS and college, really not THAT funny, and John is my opposite, he actually cracks himself up on a daily basis!

Asking about the different types of REI there are is like asking someone in the medical field about all the different types of specialists there are out there.There are heart doctors, heart surgeons, feet doctors, eye docs, ENT, radiology, neuro, blood, trauma, pediatricians, etc...See what I mean.

My field is chemistry, but I have always been interested in real estate and business, and i'm a natural born salesman (at least that's what everyone says).

I specifically said in my post that I was using "non-scientific estimates"...That said, I just took out my Chemistry set from 4th grade and should be able to generate some scientific estimates in a couple hours... :-)

Warren Buffet once said something along the lines of farmers need not understand the bio-chemistry of the photosynthesis process to grow corn, nor do they need to check the corn 14 times a day, they need only to plant it and take reasonable care to ensure it's in an environment where it can grow.

Physics and Chemistry for me, though.Its just west of Rolla.

Yet we learn poetry, cooking, some math we will never use, chemistry, history...etc.

I treated grad school like a typical "job" (40-50 hours per week, rarely working nights or weekends) and still ended up getting my Ph.D. in 5.5 years (which is average for chemistry). 

My educational background is in biology and chemistry.