Plane ticket out of Th for tourist visa in Singapore..

I'm going to Singapore next week to get a 90 day tourist visa. They say on the SG consulate website I need to show a ticket out. I have read various threads but have not seen a answer to whether this ticket out needs to be before the 60 day expire or can it be after the 60 day and before the 90 day. Also will they really except a bus ticket out? In some threads people have said you don't need to show a ticket out, again is this really the case?

I'm actually eligible for a non o but I don't have 400k thb in the bank here, would a print out of a larger amount in a UK bank do? I don't think so hence going for the tourist until I next return to the UK in 5 months.

I'm committed to going to SG now as I have bought the air ticket.

Thanks..