Setting up a wireless USB dongle for my neighbour..

I have agree'd to let my neighbour use my network. I have alittle experience when it comes to networking & wireless networking(having a wireless pc & laptop myself). I am going to go out and buy the hardware needed to setup on my neighbour's computer, I will need a USB extension cable(probably about 15meters ideally) - I cant find one as long as that so i will need to buy 3 x 5m cables, then attach a belkin wireless USB adaptor on the end of the extension cable which will be in the best place to get signals from my router from his end

My main problem though is my router isnt in the BEST place for him to access it(its in a corner which is maybe 30/40inches deep if you know what i mean) but I cant and dont want to move it because its nicely placed for my network & its all setup neatly & perfectly the way I want it - Is there a way out of this?(like another peice of hardware?) If there isnt then its simply hit or miss weither he can access it or not, Im trying to see what hurdles I'll have to climb before I go ahead and buy the hardware. If there's a hurdle I cant climb.. then theres no point in buying the stuff.

Any feedback is apreciated  


Im also just wondering, is this a realistic setup.. or would anyone recommend doing it another way? - I dont know any other ways myself, but maybe someone else does? (I have worked it out and its impossible to network this setup via cable, so thats not an option)