I do my grocery shopping once a week - For a small guy

I seem to fill a trolley pretty quick and sometime you have to buy big items.
I don't have a car so i make do with the taxi's which are great value and pretty available (Except when it starts to rain lah

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Most supermarkets even when located on say the third floor or second basement of a building have shopping trolley lift access to the ground floor or Level 1 as the Singaporeans like to put it. From there they normally have a covered walkway to a taxi rank which gets regular service. Its easy
Just take five minutes to scout the shopping centre to get the lay of the land - work out which supermarket you want to use, where the lift is, where the taxi rank is, etc and Bob's your uncle. I always hit either Giant in Parkway Parade or NTUC Fairprice out the back of Parkway Parade. Both have good Taxi service.
Have fun 8)