Valuation methodology is completely different for MF (5 units or greater) vs SF and scale is a close complement as @Ivan Barratt notes. 

@Ian Walsh I concur, human element and broad-stroke analysis is the best methodology, but I learned from running my own business for 25 years, it is best to work on your business instead of in your business. 

@Erik Nordgaard appraisal methodologies don't really vary my market.

There is no methodology provided or disclaimer on how data was obtained. 

I've been implementing the Profit First methodology after it was recommended to me by numerous successful real estate investors and speaking directly with the author, Mike Michalowicz.

Different lenders (agency, bank, debt fund, cmbs, etc) will have their own methodology.

I picked off a couple of wholesales last year using a methodology I learned from Instagram star Thach Nguyen, it works if you are persistent/consistent with it.

Have you looked at the marketing methodology and media used by each company? 

And, if you use a method other than an engineering-based study, the IRS's preferred methodology, you open yourself up to the risk of an audit.

Appraisal cost $3,300.Overviewof an appraisal methodology for Commercial:A.