Custom shipping zone regions

I am trying to setup shipping on woocommerce and having some problems. I live in a country where there are no zip codes and the shipping zones/regions in woocommerce is not so specific. What I am trying to do is say have around 20 subarbs/cities I want to setup shipping to.

Say subarb/city 1-10 I want a flat rate of $x and 11-20 I want a flat rate of $y. Everything outside of that within the country a flat rate of $z.

The subarbs are not in the woocommerce shipping zone regions. What is a way where I can add them and set this shipping system up?

Thanks in advance.