I strategically live 2.5 blocks from a United States Post Office and half a block from a FedEx pickup point. The main FedEx office is also an 8 minute walk from me. I'm bouncing around to those locations once or twice a day Monday-Saturday. It's as easy as it can be.
I use USPS for most, but use FedEx whenever it's cheaper for larger items. FedEx seems to have better rates for larger packages going to farther destinations.