I agree with BKT, but what you know and like, versus finding somehting that you CAN buy, but have no idea what its really like.
Most people can probably do with buying at a Costco or other bulk-foods retailer. If you want major supplies my suggestion is to ask around to see if anyone that you know works in a restaurant.
Obviously, restaurants buy foods in bulk quantities and usually have wholesale prices because of the quantities they buy. If you know someone in a restaurant, ask them to ask their boss to put an "extra" bag of rice on their weekly order, and when it comes in, have them pay the boss in cash and then your friend takes the bag home to you.
I'm not sure how laws are where you live, but restaurants are not licenced to distribute food like a retailer, only to prepare and serve it patrons. So there is the chance that the restaurant manager won't do it, but if your friend has worked there awhile, they usually let it slide once or twice.
I work in a restaurant, and my boss knows me, so if I ask to put some extra on the order, and pay in cahs, they usually don't have an issue. The bags of rice are about 50lbs each I guess. I'd have to check, but they're big, wholesale priced, and they come delievered to my work!
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