The sign you see above is for roasted chestnuts
天津 = Tianjin, a harbor in China, the place where I assume the chestnuts are imported from, though perhaps they are grown in Japan (note the white Japanese character on the top of the sign)
糖炒 = tang chao, "sugar roasted." The chestnuts are put in a machine like a clothes dryer with sand and brown sugar.
栗子 = Li zi, "chestnuts."
半斤80元 = ban jin "ba shi" yuan (lit. Half kilo 80 yuan)
ㄧ斤150元 = yi jin "yi bai wu shi" yuan (lit. One kilo 150 yuan).
Currently, one US dollar is about 31 Taiwanese yuan. So how much did I pay for the half kilo that I bought?