Got a similar thing here with neighbours not looking after their boundary fences and animals

On our little 2 acre plot where we have lived for 30+ years we have
6 different boundaries and neighbours.....
......years ago put in nice chain link fences as required and chicken wire to keep out wild rabbits of neighbours that could be be arsed

So, that particular neighbours, are weird like yours.
Townies playing at living in the country.
Good accountant and chef but that's about it.
Fixed his ride on mower loads of times after he has run over random stuff

Back in the day they had two large German Shepherd dogs. Alway straying and harassing neighbours livestock including my chickens.....
.....one night they got out and killed another neighbours sheep

Gathered all the evidence and handed it to local police officer( a friend) so I could keep at arms length.
They denied it all and got away with it......
......so fast forward 20 odd years and they have 2 crazy golden retrievers staying after daughters marriage broke up.
Boundary fence at the back is none existent having long ago fallen into disrepair.
The dogs often come over here and bark at me - chase 'em off with big stick

However, another neighbours horse and little dog is regularly harassed.
They are too nice to do anything and don't want me stirring the s**t

So, coming back to fences, gonna simply erect a chainlink fence inside their overgrown/dead hawthorn hedge
This has my old chicken wire trampled down by dogs and foxes from their side.
Looking forward to banging in angle iron stakes and tensioning chain link fences when not playing with my machines