If you install a purpose-made unit rather than using a portable domestic one you're:

a) going to spend a lot more money

b) going to sacrifice twenty or thirty kilos of your available payload

c) going to have to find somewhere to install it, which is going to eat into your available storage space and upset your weight distribution.

You can't put one on the pop-up section of the roof, which means that the only place it could conceivably go externally would be on the roof behind the pop-top, and the roof behind the pop-top probably isn't big enough.

Then you'd need to consider how to route power to it as well as any cutting of the roof itself that would be required to accommodate the unit's output.

Putting twenty-odd kilos high up on the roof isn't really that good for weigh distribution either.

And there's probably an argument to say that it might be more difficult to sell later if you've made lots of new holes in the process of fitting something not everybody would want, whether it's on the roof or inside in one of the under-bed lockers. See item c) above.

I'd be looking at a portable domestic unit, I reckon.

And I'd leave it until the winter to buy one, because they're much cheaper then...

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