Sumqayit is in Azerbaijan.
One can reach Sumgait by bus or taxi from Baku. Since gas prices are as low as water prices in Azerbaijan, only an estimated cost 5 Shirvan (10AZN) should be expected for a destination of Baku to Sumgait by taxi. You can bargain though, and the taxi drives can go as low as to 3.5 Shirvan.
It is around 45 km (28 mi) (30-40 min) from Baku center Targovi to Sumgait coast (Göyercin).