A few London freebies, blags and ways to beat the system from experience:
Don’t pay the £28.50 to go to the viewing area at The Shard (London’s tallest building). You can go up to one of the bars and restaurants for free instead - you’ll then have to pay around £12 for a glass of wine (a bit less for a smallish beer) but you’ll have a nice table with a fantastic view and you’ll be able to sit there peacefully taking it all in for as long as you like.
Or - if you’re feeling brave, inside the Shard foyer itself, go to the far right to the lift entrance to the 5 star Shangri-La hotel. Nod and walk confidently past the concierge and take the lift to the restaurant. In the walkway space between the lift exit and restaurant reception there are a few comfortable seats with amazing views. You’re left to yourself and you effectively get the viewing gallery experience without the crowds for the grand sum of f-all.
Another amazing free viewing place is The Sky Garden
London's Highest Public Garden
skygarden.london
You have to pre-book and there’s a bit of touristy queuing going on but again tickets are free so the wallet gets a moment’s rest which is always a good thing.
Then, take a look at the free walking tours.
Free Jack the Ripper Tour London | Experience a Free Walking Tour in London with a Knowledgeable Local Guide | Book a Free Tour Today
strawberrytours.com
You do need to pre-book as the groups are kept fairly small, but it’s free to book and you just tip the guide as you see fit at the end. I’ve always used Strawberry Tours and the Jack the Ripper one is a cracker, particularly if you go dusk/dark. You can take the family (the guides know how handle the sensitive aspects (e.g. they have autopsy photographs which they keep away from children)), and at the end just drop the guide £20 and that’s another bargain.
Not suggesting you shouldn’t do all the touristy things, just that some of the free alternatives aren’t necessarily poor substitutes, they’re sometimes better.
Have fun.