Foxes

We have been visited by foxes for a fair few nights now. They play on the lawn, poo and pee everywhere. Strangely enough the stench is bothering me more than them getting the rabbits. The rabbits are in a playhouse and aviary and the whole construction is solid, so I am sure they won't bother the rabbits at all unless I make a mistake. I am being extra cautious when I am with the bunnies and they are not allowed out of their "area".

Any recommendations to stop them peeing and pooing as the smell is horrendous?

if you have an adult male human in the house, or a close friend you can ask, get them to wee where the foxes have been. Will need to do this for a few nights runnign then now and then.. It is marking territory and doesn't always work but sometimes does.
Other thing is to get a friends dog in the garden a few times
Foxes are lovely animals but do pose a threat to bunnies and can spread diseases so best not to encourage them

When we lived in London (pre-bunnies) we had a fox visit us and leave a 'present' every single night. The ONLY thing that worked, and believe me we tried a lot of things, was to put a few drops of olbas oil onto used teabags dotted about the garden. You have to put the drops on the teabags every night to refresh them but the teabags themselves don't need replacing so often. Do this long enough to break the fox's routine. This stopped the pooing, obviously I don't know if it would be enough to deter them from coming for the rabbits.