Why don't you get your company to look at an independant staff parking company. There are plenty around who have half empty areas for half the year and would appreciate the year round income.
That way, you get away from Excel, have a service which is most likly to be better, no fines, no courts and it may cost less as you don't have to pay for each employee, just the amount of spaces required at peak time.
Simple, just takes someone to do their homework.. .Trust me, it works, we have done it.. .
