I guess I'm lucky in that I know a few GOOD local gun shops,, who can & will ship handguns for me if necessary. As noted,, "customer service" is the key phrase here.
And while it's legal for an individual to ship a handgun TO a FFL,, many FFL's don't like to receive a gun from an individual. Their business,, their choice. Plus,, there are not many shipping services that accept a handgun for shipping to them from an individual.
USPS has to have a FFL on file,, so no individual shipping there. FedEX from what we now see won't even accept a handgun for shipping. So, that leaves UPS,, which the fees are totally out of line in my opinion. They jacked up fees, demanding overnight shipping charges due to thefts of firearms BY THEIR OWN EMPLOYEES. Penalize the customers, not the thieves.
Paperwork for transferring a handgun isn't a huge deal. A gun comes in, you go to your log book, log it in. When it goes out,, you log it out. Total time to do this maybe 10-15 minutes.
But,, if you get in a shipment of 20 or more guns,, then the time it takes to sit down, log them each in, (remember,, always double check the guns serial number,, directly, so you get it correct in the log book,) then that can take a lot longer. And to log one out,, individually, about 5-10 minutes. But a business,, that has 20 or more sales a day,, that can take a big bite out of time. Time is wages & such.
It's a business, and each business has to figure out how to balance their time & (maybe) employees to where the log book is always properly handled.
A one man, small business that maybe does 10-20 transfers a week, is easier to manage than a bigger business that maybe does 50-100 a day.
And we ALL know that the BATF is easy going, allows paperwork mistakes, overlooks minor infractions, and is gun friendly. (Sarcasm inserted here.)
But it does boil down to the attitude of the business. If you treat each & every person as a valued customer,, then you'll be successful.
If you feel you can't be bothered by minor services (like a transfer) where you can easily charge $20 (or more) for something that takes 10-15 minutes for each transaction, then you will lose customers.
That's why a person NEEDS to develop a good working relationship with a couple of good gun shops. It lets the business owner see you as a valued customer. Go visit them. Buy something, even if it's a small item. Buy a gun occasionally. BRING in a friend or two. Refer others to them. In other words,, let the business owner see you as a "good customer" and he'll consider your needs much quicker.
And to answer the comment about disassembly & shipping "parts." All BUT the serialized part can be shipped like that. But a serial numbered part is considered THE FIREARM by the Feds. Big no-no to try that with the USPS.