Hate to say it, but I mostly buy on price, all in.
So, when I bought my 3010 I had a Case 580C trade in. I had decided I wanted either a 3010 with FEL, Hoe, and rear blower, or a similar Deere configuration.
The Kubota dealer checked out the 580 and gave me an all in cost of, something like $30K delivered to my door. The Deere guy priced out the new stuff very similarly, and lowballed me on the 580C, to the tune of like $3,000 (he offered $9,000 or about 25% lower than the Kubota dealer offered).
So I called him back and said, sorry, if you can't do better than that by tomorrow you lost the sale. The next day I signed the contract for the Kubota, and 5 minutes later my cellphone rang and I got a competitive offer for the Deere. I could have renegged on the purchase but, a deals a deal.
Ultimately, most dealers are happy to sell you parts or do service for you. I don't see the point of paying (for example $3,000) for the privaledge of buying a tractor from you so that you'll be somehow happier or nicer to me when I give you my service and parts business.
I work exactly the same thing on cars, and so on. The sale of a machine is a distinct thing from service: you may make the service but you don't make the car/tractor/table saw, so I want a good price on that.
And I always walk in knowing what I want. I learnt a long time ago that, for the most part, a knowledgeable sales person is most likely an indicator of an ignorant customer. Some guys are pros, some not. I will pay a couple hundred extra if a guy gives me a test drive, or whatever, but thats about the limit. On a dollars per hour basis, thats a pretty good payback.
I won't do business with anybody who I think is lying to me, or otherwise misleading me, irrespective of the savings.
And, at the end of the day, if I bring my tractor in for service, you'll do it and treat me the same whether I bought it there or not. Otherwise, I ain't coming back.