But let me be clear, there are lots of things that influence it. 20% can be good or bad depending on a number of factors, just trying to answer your question "generally".

We're an area that has great positioning for outside influence and fresh ideas. 

In the price band I invest in, this would be a portfolio of 25-100 notes, so well diversified, and an investment that you have a complete picture of and a huge amount of control/influence on your outcomes.

I understand he may influence your decision, but don't let that upset the apple cart.  

There is a myriad of factors that will influence this: age of the building, quality of the tenants, LTV that you take on the property, area, quality of construction, age of appliances, types of finishes, etc.If I were you, I would narrow down the market in which I was going to invest and analyze 10 or 20 deals.

Not only a personal, real-life mentor, but also the great authors of such books as 7 Habits of Highly Effective People, Think & Grow Rich, and How to Win Friends & Influence People (to name a few). 

Was a good influence on me before (paid off all debts aside from student loans) I feel I've moved beyond his somewhat general rules for the average American debt "sinner".

The key is you being able to influence the appraiser and have him come in at the lower end of the scale.

Perhaps cost of funds (interest paid on loan or to an investor, which could be you) influences that.

This is a third party influence for you, people know or should relize that if others who are knowledgable in RE are working with you, that's a credit to you.