From what I can see, prices are dropping around N4. 10-15-20% from the peak last year
isn't uncommon.
Firefox & Property-Bee are your friends if you want to track house priceszzzzzzzz
I reckon the quickest solution would be to remove the benches outside Tesco.
They don't seem like hardened trouble makers - more care in the community (or even special needs?) types.
ymmv...