Check the maintenance schedule for your vehicle (it's in the owner's manual or a separate booklet) to see what the manufacturer requires. Chances are everything you need could be done at a competent repair shop that is more convenient or less expensive than a dealership. Don't assume, however, that a dealer will always be more expensive. They may charge $40 or less to change the oil, rotate the tires, inspect the vitals and throw in a car wash.
It is important that you recognize the difference between an EIN and a DUNS number. Although the EIN number is used to report and pay taxes to the IRS, it is not used to establish credit for your business or to report your credit history to the credit bureaus.
Taxpayer Identification Number. A Taxpayer Identification Number (TIN) is an identifying number used for tax purposes in the United States. It is also known as a Tax Identification Number or Federal Taxpayer Identification Number. A TIN may be assigned by the Social Security Administration or by the Internal Revenue Service (IRS). Section 6109(a) of the Internal Revenue Code provides (in part) that When required by regulations prescribed by the Secretary [of the Treasury or his delegate] [ . . .