axio is a great car, normally its all time 4wd, you have to remove the shaft to disconnect 4wd, in eurpose they give you a button inside to enable 4wd...
yes on 4wd the consumption is a bit high, people normally disconnect 4wd option by going to mechanis and removing central shaft that connect to rear axles....
4wd also has low resale, people are afraid of it due to consumption issues...but you can convert it to 2wd very easily..
on the other hand, 4wd provides excellent traction....which is actually not that much a must have or required things...
if you buy it, remove its shaft and you are good to go with excellent milleage...