ooooh i thot u younger than me :P
singles can purchase resale all along lah... i think the only
restriction for how many rooms is when u buy from HDB, tat would
depends on ur household income de...
but actually for single, 3room is enuff mah... just tat the
floor area smaller lah... alternatively, join the 2 bedrooms to
make 1 mega room with walk-in wardrobe!!! heheheee
Yeah... I'm just greedy mah!
4-room is
actually too big for a single. But then that means one room
can be my bedroom, another my study cum hobby room, and the third a
library. 
I'm toying with the idea of getting an apartment with my CPF so
I can rent it out and then maybe when it's time to retire, I can
choose to either return to SG or spend half a year here, half a
year there. 
Thinking only... got to continue working hard and saving even
harder! It's not easy going it alone on a single
income. 