Actually, in the instructions for the Form 1099-MISC the IRS provides this guidance:
Specific Instructions: File Form 1099-MISC, Miscellaneous Income, for each
person in the course of your business to whom you have paid
during the year:
At least $10 in royalties (see the instructions for box 2) or
broker payments in lieu of dividends or tax-exempt interest
(see the instructions for box 8);
At least $600 in:
1. Rents (box 1);
2. Services performed by someone who is not your
employee (including parts and materials), box 7;
