http://www.ebay.co.uk/itm/CANNONDALE-R500-CAAD3-RACING-BIKE-FRAME-AND-FORKS-/350893599310?pt=UK_Bikes_GL&hash=item51b2e36a4e#ht_792wt_1170
this would be a nice starting point but a build plus parts is always more expensive than you think !
certainly not 180
@dicki started
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http://www.ebay.co.uk/itm/CANNONDALE-R500-CAAD3-RACING-BIKE-FRAME-AND-FORKS-/350893599310?pt=UK_Bikes_GL&hash=item51b2e36a4e#ht_792wt_1170
this would be a nice starting point but a build plus parts is always more expensive than you think !
certainly not 180