If you're exporting products overseas, odds are, you're relying on letters of credit through which the customer's bank ensures that the invoice will be paid once the terms of the sale are met. If you want to minimize the transaction costs and psychic toll, you'll have to stay on top of the game yourself. Here are three things to keep in mind:

* Even tiny discrepancies can gum up the works. The most common discrepancy, says Virginia Rehberg of International Transactions, an export-finance consulting firm in Boston, is shipping later than you specify. It's also the most serious, because unlike other snags that might be corrected with a call to the negotiating bank, a late ship date requires the overseas buyer's bank to issue an amendment. Buyers will readily ask their banks to do this, but for a price; if a shipment is late and the buyer refuses to waive the discrepancy, that buyer might try to get you to discount the invoice by 10% or more. Be conservative about the ship date and check all documents for errors.

* A "sight" letter of credit will help you get paid faster. Clever overseas buyers often slip in clauses saying that payment will not occur for 60 to 180 days after the banker verifies that all the terms have been met. Don't let them. To speed up your collection, ask for a sight letter of credit; with it, you can usually be paid within three to five days of the time the banker "sights" all the paperwork required by the letter of credit.

* Bank fees can be shifted to customers. Banks charge different fees for different services. Normally, you pay the fees at your bank; your customer pays his. But if you make them part of the up-front negotiation, you might be able to get the buyer to pick up everything. If you can't, ask the customer for a freely negotiable letter of credit that won't obligate you to buy services from a specific bank; then shop around for the lowest fees. -- Teri Lammers