I have been building PCs for about 22 years now. I haven't bought a new in the box computer since the 1980s. I know the hardware intimately, and if anything assembling a desktop computer is getting easier.
You would expect me to say that but the truth is that as they put more parts on the motherboard, there are simply fewer pieces you need to put on that motherboard to get a workable low end or mid level desktop computer running.
Laptops are different. I've repaired them and the smaller hardware is always more difficult to work with. You don't pull a motherboard in a laptop, they're not designed for that. Other than swapping out disc drives, memory and a few other parts most people need to keep the screwdriver away from their laptops. Leave that to some guy with the tools and most likely a magnifying glass.
I've pulled dead laptops apart and replaced the LCD a couple times before, and while it is always annoying, it can be done. Replacing a CD ROM with a DVD burner is an annoying upgrade but for the most part if you're patient and have the repair documentation you can do it yourself.
All that might explain why I have contempt for services like Geek Squad's $199 in home set up of a PC. If you do that and you're near me you're going to get a lecture, especially since I could use the cash. In Home PC Set Up is a dead simple exercise if you can Read The Friendly Manual and that manual has been reduced to a single sheet of paper these days when you buy a brand new PC.
I have a rather large pile of cast off PCs here too. Since we have a network, I use an old desktop machine as a server because it is safer than putting the "750GB Craig Drive" in an external box and plugging it into the USB port that gets stepped on by the dog or worse, me.
For the most part, people will have their machines for about 2 years, then buy a new one because the old one is too slow. Without realizing that it is installed things like "toolbars" and other "crapware" that hitchhiked onto their machine when they installed something that they really needed by taking the "Express install" instead of the "Custom install", the machine slows down with each piece of software until that 2 year old machine joins the other one that was in the closet from 4 years ago.
I live near a shopping center. In the back of the center there is a dumpster that has a habit of having an interesting amount of electronic hardware of all sorts. Since I can solder a new switch onto an old board, I've salvaged some interesting things out of that dumpster. The latest was a practically new office PC. By which I mean lightly used, almost no dust inside, treated like it was a religious object then sent to the thrift store who put it in there. I got it home, plugged it in and it turned on happily and went to an almost empty desktop.
After reformatting the hard drive from the recovery partition, the machine was fully functional and happy as a clam. I added extra memory and realized that while it is a Pentium 4 3GHz machine, slow by today's standards, it had a few benefits for me. The motherboard itself was a small one - about the size of a sheet of letter paper with some of the bottom trimmed off. The machine now had 1GB of memory and running Windows XP and was quick by even my standards. Sure, it was built in 2003, but it had a lot of life left.
All that took me about an hour of actual "work".
It gave me the opportunity to move the hardware inside that big black IBM case into a little cube of a case I've had here. After moving everything along, I dropped the Craig Drive in there and now I have a server.
Why is that important? You can't stuff a desktop disc drive in a laptop no matter how hard you try. If you are using a Cable Modem and High Speed Internet, having a network is nothing more than adding a little hardware and configuring the machines to work together.
The price was right, and it fit very nicely under my hutch on my pine desk out in the Florida room. If it were a little newer, I'd tell you how to enable Wake On Lan so you can get your machines to start remotely... but since it isn't I'm happy with walking out there to press the On button when I want access to that big drive.
Dumpster Servers can be real nice, if you know how to make them work for you. Speaking of which, it's time for me to "do a backup" of this laptop. When is the last time you did a backup of your PC? Hmm?