macbook pro 15inch retina swap or buy

I have hardly used my laptop at all. Its in perfect condition. I am a British photographer and need a direct firewire connection so therefore am offering to swap with someone who has similar equivalent to macbook pro i7 without thunderbolt. or Buy.

15.4-inch MacBook Pro Retina PROCESSOR 2.6GHz Quad-core Intel Core i7 MEMORY 16GB 1600MHz DDR3L SDRAM FLASH STORAGE 256GB Flash Storage Apple Thunderbolt to FireWire Adaptor Apple Thunderbolt to Ethernet Adaptor English keyboard

If you have F-Skatt I can also provide an invoice-for companies.or you can buy private.

It was bought in november 2012 in Sweden new for 25.000 sek im asking for 18.000Sek or swapping.

james(at)jamessilverman.co.uk office in Mölndal.