In preparation for having another go at daughter's DIY I cycled through this life-enhancing sun to the very wonderful Smith & Low hardware shop, previously eulogised here.
Last week I bought daughter's new bathroom extractor fan there - far cheaper than Amazon (who I won't use) or Screwfix (whose salesperson knew absolutely nothing about fans) - and they threw in free advice about fitting it.
For the £1.12 I paid today I not only got four plasterboard screws, but also really helpful advice about two other frustrating jobs for which I needed to buy nothing.
It's a great shame that those of you who don't live near Oxford can't visit but you can buy from their website.
Support real shops!