Diane W.

Victorian North London building? If it's poltergeist activity it'll be tied to the location history. Have you looked up what happened in that flat? Deaths, violent events, anything traumatic?

GhostHunt_George: That kit is okay for starting out. The EMF meter is the weak point - it'll detect basically anything electronic and give you false positives like mad.

Skip the ghost box for now - most of them are just AM/FM radio white noise and honestly they're more entertainment than evidence. Stick with EMF and temperature readings plus voice recording.

Description matches some reports of 'Black Shuck' or similar entities from Northern England folklore. Could be a cryptid, could be a tulpa (thought-form), could be a genuine unknown animal.

I work with thermal imaging for building surveys. Most smartphone thermal apps are actually quite unreliable - they can struggle with fast-moving objects and often have lag or frame skipping.