Hi Allan. We have a 2020 compact with an extra water tank (260L in total) and grey tank. So far we have stayed off grid for 10 days with no issues re water. If we fill all tanks we have very little payload (about 150kg). Generally we leave the drinking water tank empty (giving us 200l of water which is heaps), depending on how long we will be away and what sort of payload we require.
Re the power: we have 300ah lithium, 1600w inverter, 240w solar and slimline compressor fridge. The fridge uses a lot of power and when there is poor quality of sunlight it does become a problem. We have considered getting a generator.
As far as price is concerned, I believe CP5’s with scrub pack are around 120k ish, but I think you probably need to talk to Paul at the sales centre for a more accurate quote.