Disclosure:  I am not an mortgage broker nor am I an investor but I am a licensed real estate agent in MA.question #1: You can pay for an appraisal but you can also work with a licensed real estate agent in your area to have them do a CMA (Comparable Market Analysis).  

What makes mobile home park special (compared to apartment and houses).3.

Ask to compare to what was advertised at time of sale. 

A real estate market analysis is a study of current market values of homes, comparable to yours, that helps you determine the market value of your house.

Once you have determined that, then ask for a comparable market analysis of properties active or sold in last 6 months.

Then compare her spreadsheet vs. 

So I got out of class last night and my professor was telling me that, in order to do an income(investment) property, you will be charged with a higher interest rate compared to a property that you would finance for yourself.

(2) Does it save money when compared to buying a retail house of the same?

IMO $800 is money well spent compared to what you can save.  

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