During the Greek Dark Ages the palaces were burned, and the roads and bridges and dams mostly fell apart. There are houses, but no more palaces. But roads and bridges and stone walls begin to be built again. Democracy prevents the Greeks from building palaces or big tombs, because politically all men are supposed to be equal, and so it would look bad to have a big palace even if you could afford it. By the 300's BC , in the Hellenistic period, there are some new architectural types.
Less time is spent on temples.
The new form is the theater , and many theaters are built all over the Greek world. With the conquests of Alexander the Great, architecture becomes an important way to spread Greek culture and show who is in charge in the conquered countries. On the other hand, once the Romans conquer Greece, around 200 -100 BC , they too use architecture to show that they are in charge, and suddenly there is a lot of building in the Roman style .