Good time to renovate in 2023?

Calculate return on investment. Renovation is always earlier better than later but also whether needed to spend this money.

Is your house due soon for HIP? If so, worthwhile to wait until then as it is highly subsidised, and you can do your reno after that. If do reno now and then HIP, there is risk of damage to the new floorings etc. Even if is outdated, refurbish still can rent out for passive income and used that for reno few years later

Will wait couple years for the prices to stabilise and the global economy to turn real south. Just airing from the angle that I treasure privacy over renting out rooms to strangers at this moment though I am not against co-living where cleaning service is provided and activities being curated for the tenants.

Renovation now is better if you think of the gst increment next year. Then again, your renovation cost is very high (unless you are doing a 5 room hdb full reno), so you may want to consider lower cost alternatives.