Wireless network setup for a large home

My friend has house with four floors and owns three Macs. His ISP comes in the basement and has ethernet connections on the second, third floor and fourth floor. Only one of the Macs does not have an ethernet connection and that is on the second floor. He currently has an older Netgear wireless router with two Netgear powerline adapters to extend his signal.

I was thinking that a simple solution would be to get an Apple Extreme and at least one Airport Express to create another wireless network on the second floor for the wireless iMac. There is a possibility that a second Airport Express might be needed.

Money is not an object. What do you think of this solution? Any other suggestions will be appreciated.

 

Thank you Peteman100.

Good point.

Knowing the current wireless router is more than three years old, should I consider just replacing the router with a new router such as a Linksys WRT54GL and then add the same router on the second floor?

 

Thanks again Peteman100.

Normally, I would be more concerned about the main wireless router, in this case I am more concerned about if I should place a router on the second floor or just get an Airport Express. Decisions...decisions.