yī chuí zi mǎi mài
a one-off, short-sighted deal
a one-shot, all-out attempt
一
yī
one
锤
chuí
variant of 錘|锤[chui2]
子
zi
noun suffix, as in 椅子[yi3 zi5] "chair"
买
mǎi
to buy
卖
mài
to sell
