I just this month sold a near mint original British Brum-built 1980s boxed .177 Tempest with all the original ephemera etc, and it took ten days to find a buyer at £125 including secure insured post (£12), and as my Tempest as detailed and sold was -- and is -- infinitely more desirable and purchasable (not to mention unquestionably better made) than your friend's example, imho, I think your friend will struggle to top the £100 secure posted mark for his near-new non British Tempest if selling on here (or similar forums), so his best bet may be to ask around his non shooting associates, and see if he can get a better price selling to someone untutored from outside the air gun scene, or see what an RFD will give him for it as a trade-back against something he would prefer? He should then chalk the loss down to the steep learning curve that is air gunning (only trying to help, and this is just my take on it you understand ). Atb: G.