personally if you have the pressure washer already just go for a proper lance as said PB do all different types of fitments . I have the above lance that the hose attaches too and its not great to be honest , has good adjustment on it and maybe my hose is too long with not a massive amount of tap pressure but seeing how a proper lance works the gilmour has no chance imo compared to a decent snow foam lance , on my system it comes out very liquidy and too slow for me

hth

Mike

ps as for cheap p. washers i,m gonna get the nilfisk c110 around £50 at halfords although it may only be a 'buy online jobbie' free delivery iirc has a very good mentioning on my DW detailing forum