Hi Kyle,
The seller carry note has a 2 year required standstill (required per SBA policy) which can then convert to an amortizing term loan once the 2yr period is over. During the 2 year standstill the loan CAN accrue interest at a rate agreed upon with the seller. What the loan converts to after the 2 years and repayment terms is typically up to the borrower and seller.
Lender policy may vary. I have done loans where the a lender really doesn't care what the agreement is i.e. payback over 3 years, 5 years etc. Others tend to like the seller note to be repaid at the same terms of the loan, which I see most often in business acquisition loans (they go up to 10 years terms w/out real estate). Others are fine for example matching the seller loan amortization to the term of the loan, but allowing for a balloon where the loan can essentially be paid in full well before (the lender may even be in a position to refinance it out for you both if the numbers work).
The SBA policy is basically the general guidelines for all lenders to abide by and then each individual lender will layer on their own preferences to meet their credit risk profile. This plays a big part in the type of financing that can be done or industry. For example, some lenders may want to stay far away from the hospitality or restaurant industry, while another lender may love it and have it be a main focus of their business.
Since this is a new purchase (and currently not renting the subject space), you will be required to put down money. SBA and USDA (pretty similar in many aspects) can allow as little as 10% down, however generally speaking I think it was sound advise from Scott that you may need to put down more down, possibly up to 25%, which of course can be a combination of your money and seller financing. Say 10% you and 15% seller. The SBA also has 2 programs for real estate purchase - 7(a) Program and 504. Each has their advantages.
Talk to lenders and they can provide insight to their potential structures (interest rate fixed vs. floating, seller note, down payment etc.). Also be prepared to share the business plan and likely need to do at least 2yrs of projections since this is really a new phase of the business (consulting to now operating a venue).
Hope this helps. I am new to bigger pockets and posting, but been all over these boards for months for my own personal investment knowledge.