For KL property ah...quite frank with you, RM50k is insufficient for 1.2k sq ft unit if you're looking for interior designer and you want "designer" look (a lot of modification and built-in carpentry) that's "own-stay" quality.

Minimum is around RM80k++

If contractor only (managed by yourself), doable, but you need to be smart about project management (when to bring electrician, painters, cabinets etc.) because errors and conflicts in schedule can easily balloon your costs.