Starrett City has an extremely small post office that can get quite crowded. Lines can be especially long during Christmas and tax season. TIP: If you want a big package delivered to you in Starrett, It is suggested you avoid using the United States Postal Service for this type of delivery. If you are not home, they will leave the package at the Canarsie Post Office and not the one in Starrett. You will have to go all the way over to Canarsie for pick-up. Use UPS or another courier instead if you have the choice.
A couple of buses run through Starrett City, which is pretty important because Starrett is located in the middle of no where and you need a bus to get to a subway station...that is unless you don't mind walking 30-40 minutes through a less safe neighborhood to get to the nearest train. There is the B83 bus which has a last stop at Broadway Junction, and the B82, a bus that stops by the Canarsie L train station. You also have buses that go straight to Manhattan during the mornings, but of course it's going to cost you more.
There are two banks located in Starrett. This one is the HSBC, which is right on Pennsylvania Avenue. The ATM machines in this branch have lousy privacy. They are situated in a way that people walking outside can see you input information from the window. Just look at the picture above and you will get the idea. EDIT: They have since put up a panel to fix this.
This Citibank is located right next to the Radioshack on the far end of the mini strip mall. This branch has plenty of ATMs and people inside to assist you with your banking needs.