K-Pro-Mowing,
You may need to be a little more specific in what your expectations are for a "Commercial" ZTR as that term is widely used with no definitive qualifications. For what I consider true "Commercial/Professional/Industial" grade as sometimes described by different manufacturer's to define their different Models/Series versus what they describe as "Residential/Homeowner" Models/Series I would tell you that $5100 for a 52" is unrealistic(for new) and "maybe" for a smaller 42-48". I decided I wanted a new "Commercial" ZTR and began with a $4k-$5k budget. After looking at 4-5 different brands and talking to dealers I discovered that I was going to have to convince my Financial Advisor(aka, the wife) to approve an expenditure more in the $6k-$7k range(I wanted a 52-54"). If I were to be looking today, I would not end up with the Gravely I have because Spring(versus Fall when I bought) is a "dealer's market with little incentive to give deals because of the supply & demand. And the ZTR I bought had a $300 price increase in 2013. I ended up within my budget for a 2012 last Fall, but consider myself lucky to have decided to buy when I did. Good luck finding something new at $5,100 and Id be glad to offer up some suggestions for some high-end 52" Residential units or entry-level Commercials with smaller decks. Note that some of what "I consider' high-end Residential(with a few Commercial components) may be considered by others as Commercial units based upon my first sentences. It is you that will have to define the build and components that are important and mean "Commercial" to you.
