The design of a good app should have only 1 Company table to hold all the Companies. One would assume that there will be lots of companies and they will each belong to just one Company Type each. is that the business situation?
If so then the relationships are
1 Company Type has many Companies.
1 Company has many Orders ( or whatever your form is collecting.
Typically, you might want to choose a Company Type, such as Cat Dealer and then see a conditional drop down (Sam's approach) of just the dealers who are Cat Type Customers. If the list of all Companies who are Cat Type is a short list, well then it's short, but I assume that for other types of dealers there will be more than 1 to choose from.
