I wouldn’t buy that frame for £50, the handsome dog yes.
On feebay if you hang about you will see decent frames come and go, I once got a 1998 pristine condition orange msisle for £75. Sold it of course but you do get a lot of good frames.
My email is in my profile if you’re not going for the handsome dog I will help you track something down on ebay and tell you the right questions to ask.
Good on you for helping get your mate into biking, my mate crashed his car yesterday, so I had him round last night for a visit, he came at 7:30, I checked his bike and the frame bearings where knackered so where the front wheels bearings.
4 hours later both the frame and the front wheel was sorted and half a bottle of wine was gone as well as some expensive cocoa powder mixed with honey. All I had lying about 😯 .
We had a good laugh though and his spirits lifted and he spent today at inners, I will help out all that I can if you need a hand let me know 😀