Hi Jack. Glad you want to be involved! Always good to have more players getting in on this good thing.
tbh I think I've made this one a bit too hard. I wanted to highlight this interesting and unusual signpost, but thinking on it, it is a tough one to find.
The signpost points west - east. Hove and Worthing are to the west, sure. But London is actually due north, and Patcham is to the north and east (and more northerly than easterly).
The house behind the signpost always seems to be flying a flag, but I didn't look too closely at what the flag is. It's located to the west of the London Road.
Hope this is enough to go on... I can give more clues later on if necessary.