Johor is cheap compared with Kuala Lumpur. A full house can be rented about $150-200 fully furnished. If you prefer room it’s around $50. All in all 400 will be enough monthly, if you want little bit above average living.
Do a research online ourself, don’t just follow speculations man. Johor is not that cheap, and cost of living is crazy as well. Check online, so many site to look for accommodation, do thorough research before you move