The message
from Tony Williams contains these words:

At the time that the owner died, the hedges were cut down by one
neighbour to the extent that there is now only 12-18" of stump
above ground. The hedges were obviously mature (the stumps are
bloody thick) and closely spaced.

Put a row of fenceposts down the hedgeline, (along the
property boundary if possible), re-fence it, and allow
the hedge to grow back again.

Personally I would go for the option that uses the back of the garages
as part of the fencing.

'Pigwire', from agricultural merchants, is probably the
cheapest fencing. You can recognise it as having mainly
large squares, but with small ones down the bottom (to
stop piglets getting through). Pigwire is about 3ft high
so you may need to overlap it if the dogs are agile.

I know that as sheep netting. Comes in 50 metre rolls. Can't see any
particular reason why it can't be fixed directly to the back of the
garages and with 50m to play with there should be enough to give 2 runs
and double the nominal height.

--
Roger Chapman