The dispenser is without water filter, hence no maintenance cost. You need to get Aquaphor Crystal Eco as the main filter, maintenance cost for Crystal Eco is RM 450 per year.

What I learned, through the hard way.

1) As long as the claims / reports is coming from the seller, take it with a big pinch of salt, always do your due diligent.

2) We are blessed with the power of internet, always check for the 3rd party sources, for example NSF (national sanitation foundation) & WQA (water quality association)
---> http://info.nsf.org/Certified/DWTU/ (standards body and also regulator, like a international SIRIM, they do safety testing on all kind of products)
---> https://www.wqa.org/find-products (conduct testing on water filters based on NSF standards)

#Diamond, Coway, Espring, 3M, Culligan all got their test reports published there, black & white and no gray area.....
3) Play safe, be extra cautious...be technical if you must, study the standards: http://www.nsf.org/consumer-resources/wate...eatment-systems

#You will notice Cosway Hexagon claim they fulfill the NSF standards....the salesperson probably will they you they are also NSF certified, but when you check what NSF-44 means, you will 
#You will wonder why Cosway is not found in the list, 2 possibilities, they OEM...try searching for the model name and you will find out it is manufactured by a Taiwanese company, only passing the chlorine reduction test
http://info.nsf.org/Certified/DWTU/Listing...ModlStd=ModlStd
#There are many brands claim they pass NSF but not found in NSF & WQA (both their brand and model names)
#when you go deeper into the rabbit hole, many of the alkaline ionizer (kangen / VWA...etc etc) were not passing any of the standards, you will soon realized, all the claims can be debunked by just searching for the real info...

4) It's not that difficult, just remember to check and double check and cross check, especially you are buying something for the whole family