I was told by a groundsman that the best way to get foxes to move house is to go out and do some gardening ... get really sweaty in an old t-shirt ... then do it again the next day in the same t-shirt (NB: do not wash the shirt) - keep doing that for a week or two until the shirt is REALLY stinky!!!
Then cut it up into little squares, keep them in a plastic bag to preserve their 'freshness' and then scatter a few around the areas you don't want the foxes to be.
They know to avoid humans, so having little stinky pheremone bombs littered about will likely spook them and they will stay away.
Refresh your sites after it's rained to keep coverage going.