Originally Posted by
flatlander
Consider Covent Garden for shopping, because it has the London Transport Museum, where you can divide yourselves between shopping and urban transport history
You go in the museum while she shops.
Speaking of the London Transport Museum, you should prepare yourself for two kinds of sticker shock at London museums: shockingly high and amazingly free. I had an out-of-date guide that listed what I thought was a reasonable admission fee, £8 IIRR. When I arrived at the museum I was stunned to discover that daily entry passes no longer existed. Only annual tickets are available, at £16 a pop. It may have been even higher when I was there in 2013.
I couldn't bring myself to pay US$50 for a couple of hours' browsing for two, so my wife and I proceeded to the free Victoria and Albert Museum.
The V&A, British Museum, National Gallery, National Portrait Gallery, Natural History Museum and many others are free, though I always drop a few pounds into the contribution slots. Non-free museums are almost universally very expensive. You're spending a lot more money to get to and stay in London, so these costs don't really increase your total expenditure all that much percentagewise. They'll feel less like a punch in the gut if you're expecting them.