There are NO hard and fast rules. It is whatever it says on the deeds, but even that doesn't always indicate who is responsible for which boundary. If the fence is erected exactly on the boundary then it is a party fence and the responsibility of both parties. If it is erected on the other person's property then it is theirs.

Rule is normally the left hand fence is yours. There are exceptions and other issues but essentially if we look out of front or rear of say a terraced house.. The left hand fence would be your responsibility and ownership.

The party erecting the fence is normally obligated to put the better-looking side toward the neighbors, so if you can see the posts and hardware, it's probably yours.

I wasn't aware there was a typical saying whose is whose fence... it depends on your title deeds, boundaries should be clearly marked and whose responsibility it is to maintain etc.

Fences are normally shared

have a look at your house deeds

Read these 2 links:

all your fence are belong to us

What ever your deeds say - there is no 'general' or ' normal' - look to your deeds