Tips for buying hardware?

[MS]

Opening a laptop can be quite an adventure.
If there is no upgrade ports under said laptop, I would NOT recommend a "normal" user doing this, at all.
I spent 2+ hours one time to open (well dissasemble...) an HP laptop just to clean the fans and I open laptops frequently.
Other laptops, you have to remove frame, keyboard, etc. just to add memory. Some laptop conceptual engineers should be fired sometimes.

There must be a reason to it. My guess is that statistically, laptops are perhaps upgraded marginally compared to the desktops, as well as stereotypical laptop users are less techy involved, compared to the desktop users. Which is why, for the costs of manufacturing complex parts, as well as making a design to enable easy upgrading, it was discarded. I do not even know really if there are any laptops nowadays having any easy upgrade access ports. Similar as with cars. Mind majority of modern cars resemble a ball more than a rectangle. This comes due to interior ergonomics calculations, meaning, it is easier to build a smaller car that can contain more, this way, using less materials at the same time. Optimization.

EDIT:

When it comes to the warranty, it is good to respect it. My 'Inspiron 15-5567' was at the warranty service two times before it could be considered good to go. They replaced the fan and then the motherboard. Think if I had to pay for it myself. Some could argue this is the reason to choose the used equipment instead. Well, used equipment is not equally good to everyone, depends on how much does one know what one is actually buying and what are the possible quirks, which could emerge time soon in the future, specific to the hardware.