There have been some words of advice that indicate that having address space is expensive in relation to setting up a data centre. I'd have to say I disagree. Anyone setting up a data centre will be face with costs for racks, air conditioning units, power supply, rental of premises, cabling that make the APNIC fee of US$1250 (NZ$1700) for up to a /22 look like small beer. (Yes, I know there's a one off fee of US$2500 as well) Weigh that against the cost of renumbering your own and customers' infrastructure somewhere down the track - say in a year or two if you're wildly successful because you've got a better deal from another upstream provider or you're royally hacked off with your existing one and it doesn't seem nearly as bad. Remember that once you go to a customer and say 'we need you to renumber' someone else's numbers are just as easy for them to change to as to yours.