"We've never signed any kind of an agreement without making changes," says Tyrone Magby, IT sourcing manager at Fiserv Inc. in Brookfield, Wis. Key examples include the addition of indemnification clauses and guarantees that the maintenance terms are tied to the net price and not the list price of the system, he says.

8. Don't Be Rushed.

Don't allow a vendor to hurry you or corner you into making a deal to meet its timetable. "We don't like to be forced into [meeting] a date," says Magby. "We don't play that game."

"If a vendor gives you less than a month to do a deal, you'll almost certainly lose financial benefits to your company," says Schleiden. That's because 30 days or less isn't enough time for customer companies to work their own provisions, like audit requirements, into a contract or to negotiate and "make the vendor sweat the competition," says Schleiden.

9. Run the Clock.