Cost of living in Malaysia is low, especially when compared to other countries nearby. Renting a place to live will cost much more in the big cities, especially Kuala Lumpur, or KL as the locals call it.
When it comes to food, whether bought at a store or market, or eaten in a restaurant is pretty cheap. Once again in the bigger cities it will cost more but still low when compared to back home. Street food is very popular and significantly cheaper than restaurants.
Transportation is also very affordable in Malaysia, with taxis readily available in most large cities and in Kuala Lumpur, trains and monorails as well. Monthly transportation passes are a good way to go for convenience and price.