Possums and Bandicoots - deterrent trials

I have a real problem with Possums & Bandicoots, not in my veggie patches; I have fenced all these off, but in my gardens and lawns.

We have divided our backyard into a couple of different styles. We have a Cactus & Succulent area and a Tropical Garden/Rain Forest area as well as the veggie beds.

The front courtyard has lawn and is surrounded by a boundry garde

n bed (approx. 4m x 8m) I have planted an array of flowers in the edging, as well as a hedging plant in front of the Japanese Maple we planted not long after we moved in.

We have put a 10cm in depth Cream pebble's (size 20-40mm) down to give it a dry river bed look with a curvey line of gold Cowra river pebbles. It looked great, until the Bandicoots decided to see what was under them. Who thought they would do so much damage to pebbles. I thought they would be to heavy for them to move, but no.

The Tropical Garden/Rain Forest area has been mulched with Cy

press Mulch, which smells divine and looks great, until they the Bandicoots appear.

What I have tried to deter the critters!

******as I have a cat I have to be careful what I use as kitty needs to use the garden when nature calls******

Passionfruit Vine

Camphor - those little ones that you hang in your closet.

Result - made the yard smell nice, but did not work as a deterrent, FAIL.

Multicrop SCAT Bird & Animal Repellent.

Result - ate every leaf on the plant, FAIL.

Garden Beds (rainforest, cactus & courtyard)

Pine-O-Clean

Result - smelt nice and made me feel like I had at least sanitised the possum pee, FAIL.

Dynamic Lifter/Dyno Fert (Chicken poo pellets)

Result - fertilised garden only, FAIL

Chili Spray - homemade

Result - will let you know, I have only just made it and sprayed it on a few small areas in the gardens.

There are a few more things I can try and will if the chill does not work.