Rework Form (1 Viewer)

I have decided to re-make a table and at the same time, remake the form.

On the form, I will have three fields that will effectively help drill down to get the right data.

Brand (John Deere, Kubota, etc.)
Model (there are 20 different models in JD alone, as well as other brands)
Model Desc (there are multiple model types for some models)

I have a flat file that I want to use to allow the salesman to drill down.

The end result is displaying the purchase price and hour information.

Is there a simple method of using the series of drop downs to get to the correct model?

Yes - use cascading combo boxes
a) Brand
b) Model - filtered for selected brand
c) Model Desc - filtered by selected model

See this link for an example http://www.fmsinc.com/microsoftaccess/forms/combo-boxes/cascading.html

From the way you've described this, perhaps it should be split into 3 tables