Living cost in Malacca

Living cost varies almost as much, or even more, on the type of lifestyle you're seeking. I find that KL is very affordable, but my wife (born Malaysian) and I live like the the locals, eat at food stalls, shop at wet markets (at least my wife does), live in a simple low cost terrace house (my wife bought before prices went crazy), and drive locally made cars. I use a scooter to get to/from work to save on petrol.

Others that rent condos in town, hire drivers, eat in 5-star restaurants and like to drink (alcohol can cost more than a meal in most places, I remember paying RM6 for my meal and RM20 for a couple of beers back when I used to drink) and drive imported cars. 

So without knowing your lifestyle there is no way to answer your question.