UK money. Still that works out to about $400k in us dollars. You can find better deals in the US, but probably none with tunnels - and unlikely to be places you want to live though not bad places (bad places in the US that would be around $120k)
I once came across a middle-of-nowhere midwestern house auction listing by the US government. It came with a detached 5-vehicle garage, and an attached multistory underground hole I assumed was a missile silo. I can't remember the exact starting price, but it was significantly lower than $400k IIRC.