In the long run, you are better off and will save money if you just make the system yourself, installing the exact features you want, and leaving the filtration options open to what is most readily available in your area. The very worst that can happen is you are left with a water filtration system and a dehumidifier that you use separately.
What are some other reasons to produce your own water? If you do anything in a lab, or anything with hydroponics, having pH controlled water with consistent quality you regularly test and know exactly where it comes from is important. If you take a more scientific approach to cooking, for each controlled variable involved, there is less guess work. Also, every once in a while, there are terrible floods here that cripple the supply chains of places like 7-11 and Family Mart where you'd usually get your bottled water. With a water generator of your own, you'd glide through these rough spots and probably have some to spare for others around you.
1. Check out available dehumidifier & filtration systems.
- keep in mind that the condenser coils might have to be swapped out for stainless steel coils
- the holding tank might have to be removed or switched out depending on what design is decided on
2. Ensure all surfaces touching water are chemically inert - stainless steel or glass.
3. Locate reliable water quality testing services.
What might need to be fabricated? Holding tanks and coils. Depending on the dimensions of the dehumidifier and the water filtration system used, a custom shelf might need to be fabricated as well.