I can't advise you of any company that includes campervan damage in their travel insurance policy maybe someone else can help you with that. Having some experience in hiring motorhomes before basic insurance has normally been part of the hire charge and depending on how much you wish to reduce your excess they will quote you a per day price. If you opt to take the risk and not reduce the excess you will pay more up front if the vehicle is damaged. Remember even when taking the full insurance excess reduction there are some things that they will still charge you for i.e. single vehicle rollover, roof damage, replacing a tyre, windscreen replacement or chips. To reduce your excess to zero the Jucy website is currently quoting AUD$30/day. The "take the risk option" is AUD$0/ per day with a AUD$5000 excess, they will normally take a credit card imprint equal to the excess amount which they can charge against if something were to happen. Here is a link to a website that will cover the excess and all of those other things that are not normally covered in the hire company wavers for a lot cheaper price. Ask if a sat nav, Apple car play/Android system is in the vehicle as this would be the best way to find your way around especially if you're alone. I hope this helps, take your time travelling down the NSW north coast there are some beautiful little towns and beaches, call in to Byron Bay you might spot a whale from the Cape lighthouse (depending on the time of year). Enjoy your trip......

https://tripcover.com.au/campervans/

BB has covered most of what you need to know but there is one thing more worth mentioning.

When you hire a campervan (or any motor vehicle) there is a basic excess of a few $k, probably around $5k with a camper van? The campervan hire company will give you an option to avoid paying that excess by paying an additional sum of $30 per day or some similar sum. If you take that route then the following will *not* apply to you.

If you do not pay the extra to the campervan hire company you can either take the $5k risk yourself or some travel insurances will cover it. In either case the campervan hire company will require an imprint of your credit card (or an electronic equivalent) and the moment they are informed you have had an accident they will slap a charge on your credit for the whole $5k (or whatever the excess is) and only much later will you be able to retrieve that from your travel insurance or the balance from the hire company if the repairs were less than $5k.

If the sudden loss of $5k from your credit card is going to make a difference to your cash flow then it may be worth obtaining a new credit card with a low limit and, before you leave home, paying enough into that card to cover the hire cost but not the excess. eg. If the hire cost is $3000 and the credit card limit is $1k then pay $2.5k into the card so you have an available balance of $3.5k. This will pay for the hire but will not allow the hire company to sequester $5k of your cash before they even know what the damage is.

Thank you!  I'll pass this on to my travel agent.