There's no way for toy shops making only hkd 10-20 profit! That's unacceptedly low.
One of my friends used to have a toy shop at Richmond. He told me toy shops in HK often get their goods from distributors in this way:
Take an example of Super Stealth.
The suggested resale price in Japan is 14,800 yen, which is roughly hkd 1,036 (100yen = hkd 7). Distributors sell to toy shops base on 14,800 yen, with the currency exchange rate tuned to 100yen=hkd4 - 100yen=hkd5, depending on the quantities.
By selling a Super Stealth at hkd 1,000, toy shop still makes hkd 260-408 profit!!!
Sadly, my friend didn't sell any Yamato valks or I could get them at even lower prices....