Recently my cousin Singaporean facing stress to buy new bto flats.

If he has time then should live the singapore dream and bid for a BTO! Many fail alot of times, sometimes if you are urgent, can look for MP to see if they can help due to high number of failures.

Depends on level of urgency and income really

Get a resale, it's the same price or cheaper than a BTO. Just reduce the number of rooms =P

I think if really need the house to stay in, can either rent, or buy resale first, but calculate the payoff for each choice. Resale may be more expensive, but is a no choice if really need a place to stay in while keep trying luck at bto. Othereise, continue to stay with parents if available.