Any recommendations of a chain & ground anchor for ~£50 total?
No.1 concern is of course security.

Nope but if you want some worthwhile, try Pragamasis, even Kryptonite’s ground anchor is the best part of £50

Not if you’re spending £50 total it’s not.

If security is no.1 concern then a concrete in ground anchor to start and then you’ve blown your £50.
An anchor / chain / lock that is decent will be way more than £50.
If you can only spend £50 quid for it all then it will be a compromise

Well what is the best for £50, or something close.
It is a last, final deterrent and not for a push bike.

Is this for pure piece of mind, or insurance?

TBH I’d want either of those I’ve linked to (/mentioned) above, but you might try looking through the http://www.soldsecure.com/search?name=anchor&action= site to see what other they rate, as I’d suggest if it’s not rated, it’s kind of not worth buying. Other option for a ground anchor is an old U bolt or a loop of (high tensile?) steel concreted into the ground, this will be the cheapest choice.

For big blustery but probably rubbish in the face of a hacksaw, the likes of “Range” stock big chunky chains & Aldi have been known to sell similar, with their cycle range offers.

Drop me an e-mail mate, I may be able to help with regards to a ground anchor.

I got turned over a couple of years ago, they took a two grand bike and I work for Paslode so they copped for five or six tools as well – no security at all.

I mentioned it to a customer who then went and developed a really good little ground anchor, marketed it but then it kind of went a bit flat as we both had full-time jobs.

I’ve got about two dozen of them sat upstairs doing nothing, I’ve put four in the garage for both the bikes and an expensive gas BBQ we bought last year.

They retailed at £45 but I paid £22.50 each for them so you can have one for that posted if you want, I’ve also got some chemical resin to set the bolts with if you want to make it a permanent fixture! Gives you a few quid spare to get a decent lock/chain.

Ive dug a hole and sank a chain in then concreted around it, its secure but as with anything its dependent on how keen they are

As per what Duncan says, if they want it they’ll have it. Whatever you buy will just slow them down, I’d like to think the bright red anchors I’ve put in the garage may make them think twice about it but when they come armed with cordless angle grinders there’s not a great deal you can do, unfortunately 😥