I'll be using a pass-down playpen. Do mummies here have any ideas what can/must i buy for this used playpen?

There's already a mattress provided, so i'm thinking a fitted sheet is a must. Do i need to buy the comforter set for my newborn baby?
I bought a dimpled pillow and my mum made me a beansprout pillow.
Do i need to buy bolsters and blankets? What about toys and mobiles...what do you all suggest?

And when do you all think i should set up the bed? My hubby say set up when baby arrives..but i think it might be a little late, cuz by then there's so much more to attend to!

Hope you all can help me out on my questions! Xie Xie..