Most of the problems I was made aware of had to do with international trade, not domestic trade.
One guy I met said he privately imported (some of) the goods needed to build his home by containers from Europe because buying them locally was like double the price, because that meant buying them from essentially government-party-appointed resellers.
I obviously have no way of verifying the truth of that statement but you did ask.
> One guy I met said he privately imported (some of) the goods needed to build his home
Someone having their own home built in Singapore would have to be extremely wealthy. And the fact that shipping goods from Europe made any kind of economic sense suggests these were luxury goods.
So, yeah. I'm going to entirely discount this anecdote.
Singaporean here. Singapore has always be a free port. Anyone can setup a business and legally import items. There are no such thing as “government-party-appointed resellers”.