Q: I'm starting an exporting firm where I bring the business knowledge and contacts to the table and my partner brings the finances and flagship product. I plan to run the company, and he will share in the profits. How do we value our contributions when we split up ownership in the company? --S.C., Hoboken, N.J.

A: First rule when structuring partnerships: There are no hard-and-fast rules. Some partners apply the feel-good method and split everything 50-50. Others buy into capitalism's bottom line -- the gold rules. Throw 10% to 20% to the service partner for sweat equity, but base majority interest strictly on the financial contributions of the money partners. Neither approach is ideal, experts say. What starts out as feel-good turns into feel-bad when the money partner's return on investment bogs down. When the good times roll, the service partner pouts because his or her contribution gets short shrift. "Even if they have the best intentions, partners can either be overly selfish or not selfish enough" at the startup stage, says William V. May, president of Seattle-based Stonemark Investment Bankers.

Better to sit down with your lawyer and CPA and draw up a list of the assets that each partner brings to the deal. Don't limit it to cash or financing. Add things like patents, customer lists, and entrepreneurial experience. Do you have vendor contacts in an industry where suppliers give the cold shoulder to new companies? Can you secure a fantastic lease on a great location? You're putting something of value on the table.

Put some numbers behind your knowhow, says Tom Cain of Wheat First Union, a regional brokerage and affiliate of First Union Corp. based in Richmond, Va. How much would a commercial real estate agent charge to secure that lease? How long would it take to build relationships with vendors? Once you've calculated the market value of the services each partner provides, you can split up the equity more fairly.

Watch out for a tax-related booby trap that some do-it-yourself diehards fall into: If you don't structure the deal correctly, the service partner could get stuck having to declare the value of the equity interest in the company as income -- a potentially very expensive mistake for someone who may barely be drawing a salary. "This is a disaster that's best avoided by going to a lawyer who's familiar with the creation of new businesses," says Joel Luber, an attorney with Caplan & Luber LLP of Paoli, Pa. A specialist can also suggest flexible business structures and constructive approaches to divvying up shares. Another bit of wisdom from May to keep in mind: "There are a lot more people with money willing to fund a business than there are great entrepreneurs with great products, management knowhow, and great ideas." Translating that view into equity is the entrepreneur's challenge.

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