I've read lots of off-hand complaints here about the problems long lines at post offices cause to us PBS people who are mailing multiple media mail packages. And that's where I started out too. Then I found several local Contract Postal Units (CPU's) around town inside of private businesses. And the waits there are almost non-existent compared with the PO's. For all I know this may not be generalizable over all CPU's everywhere, but if there are any CPU's in your area and the post office push makes life harder for you, try the CPU's. I usually walk right in and up to the counter, no waiting, excellent service. Private enterprise strikes again.

just remember that they are NOT postal workers, they are NOT well versed in postal rules and regs. They are fine and dandy to buy a quick book of stamps or mail a simple parcel, but they are hopelessly inept at handling more complicated. 

I haven't seen a CPU in our area for years.  Unless UPS counts?

Thanks for the suggestion to use the CPU. I doubt those that work at these locations are any less informed than the postal workers at my post office. The postal workers at my post office are definately inept at doing anything beyond selling stamps. My international packages make them so dumbfounded. I get told I have the wrong custom form. (I know which to use and the superior even had to tell the woman that it was correct). I use online postage and the APC machine when I can to avoid the incompentant postal clerks. I wish the postal employees knew how to do their jobs but that is not always the case

If you want to avoid the lines, buy a postal scale for about $10 and buy the postage either from PBS or PayPal (cheaper). You can purchase first class, media mail, and international from paypal.com/shipnow and it does not have to be linked to a PP transaction. The rates are cheaper than the post office for first class and international and none of the extra fees that PBS charges. 

I'm sure things may differ elsewhere, but the folks at our local CPU (about a quarter of a mile from our house) are much nicer and friendlier than the poor, harrassed post office people. And in particular, they let ME tell them what to do and how to do it! And no waiting! But of course there's nothing at all complicated about what I'm doing or asking them to do. Entirely pre-wrapped media mail books with the odd first class for very small books. It's all computerized, which they know well how to do, they know I don't want tracking or any other services, so it's simply walk up to the counter, ring for service, hand over the books and swipe my payment card. With smiles on both sides. And no mistakes.

Why don't you just weigh and add the postage yourself?  I keep all kinds of stamps on hand, and when that isn't enough I can use Paypal to ship or PBS postage.  My local post office (which, by the way, has extremely friendly people) has an unoccupied station where you can do prepaid drop-offs only - there is always someone in the station next door who nods me on to indicate they have accepted the package(s).  No waits even the week before Christmas.

My issue with the CPUs is that often they have a big USPS sign out front, but are almost never open other than, say 10 am to 4 pm M-F and almost never have blue drop-off boxes.  Fine if I'm in the neighborhood and they are open, but oftentimes I pull into one thinking I can mail a package or drop off some letters and it is closed.

don't they also usually charge an surcharge to the postage rates?

A CPU does not add any surcharge to postage - they are contracted by the USPS to provide service and receive a percentage of postage sold from the post office to provide the service.  So you will not pay extra to use a CPU (contract postal unit).  Usually, a CPU is added to an existing business because it brings in a little more money and lots of foot traffic  I worked in both a CPU and a private postal center.  The private postal centers (such as UPS or PostalNet or whatever) add a % to the postage so you do pay more.  This % is set by the private owner, so it can vary from place to place.  When I worked at the CPU, there were some customers who insisted we were charging more. If they were so inclined and went to the post office, they found out our rates were exactly the same. Usually they would become regular customers once they had convinced themselves they weren't paying more.  When I worked in the private postal center, if people asked, we would tell them that "Yes, we add a surcharge."   If they were so inclined, they could go to the post office and pay regular rates.  You can ALWAYS ask.  Keep in mind, some customers would get angry that a private company would charge more.  That always perplexed me because no one was forcing you to pay extra.  You have a choice to go to a post office and pay regular rates. And economically, the business owner has to cover labor and real estate costs and make a profit.  Business is business after all.  If they didn't charge more, they would lose money on every postal sale. So, a CPU is paid by the USPS to provide a service.  A private postal center covers their costs with a surcharge.