A challenge: wireless setup

I have to setup the following wireless network and i wonder what my

options are:

Simply said: i have to give a portable wireless access to a central

site from basically two locations, each across the street (range 100

meter and portable PC is inside the building). One building has walls

of glass (showroom), the other building is a standard, solid brick

house (common house in Europe). The portable has wireless build-in

(Centrino). The environment is also quiet challenging: The central site

is a car garage, so lots of metal :-) :-)

For which solution would you choose:

central site. No other devices across the street. Will the portable get

this range ?

remote locations, bridging the whole thing together ? So connecting the

portable via wired to the access point (i was thinking about WAP54G,

with custom firmware to boost transmit power)

build-in wireless of portable)

Regards,

Geert