Went out to buy another 250ml tin yesterday and paid £5.99 for it.
When I got home I noticed that the previous tin still had its price sticker - £9.49 and I think it was bought at the same store or another branch of same store about 3 years ago.
Perhaps the almost-used tin was mis-priced in the first place, or have Bostic fiddled with the content ?.
Since it uses very strong solvents, I wonder how they cope with VOC2010 anyway ?. The wording on the tin hasn't changed, but has slightly different warning symbols for inflammable etc.