In any complex sale, there are 10 rules of selling you must always keep in mind:
The mother of ALL rules:
Whenever the prospect asks you to do anything that involves expenditure of your resources, know exactly what will happen next before you do anything.
Prospects lie with fat words. Accept none of them.
Always know where you are in YOUR process. After each call you must update your situation awareness:
Sell to prospects; teach customers.
Stop telling and start selling.
If they can't tell you the cost of the problems, they will not spend money to fix them.
If you didn't create the specifications of the RFP, then you are column fodder.
When you're not last in the beauty parade, you lose.
The truth and the money for me is at Level 3+.