Note just for info - this is the likely order of effectiveness
1) Cpu repaste - Made the biggest difference for me. All of these Laptop companies use crappy paste that dries up in a year. Good pastes dont dry up. Good pastes are not expensive, certainly not compared to laptop costs. So the only reason that i can think of on why they use crappy stuff is to get more sales. People who dont know will eventually buy a new one as your laptop heats up. You only need to repaste
once. Dont need to do it every six months.
2) Dust - This depends on laptop model. My old Toshiba had a big chunk of dust in front of the fan exhaust. My more recent HP is much better and didnt have any significant dust on fans. So no need to clean HP every six months.
3) Cooling pad - Cooling pads are comfrotable to use, so get them anyway but they dont make a major difference. Unless you use a desktop fan blowing right into the intake
I am not a hardware guy either. Laptops are probably the first thing i opened up. You have plenty of good videos in
youtube.
This one
here is very nice that shows how to do it properly in an organised manner. Worth a look even if laptop model is different.
Anyway, its a bit of work and not all may want to do it. i am just saying its not difficult. i prefer to be not dependent on them and its fun to do once.
Just ask them to use a good cpu paste (a good enough cheap one will be ceramique 2). Unless your cpu fan assembly is a dust magnet you dont need to do it every six months if done properly.
Finally, if you dont need mobility, use desktops. They are cheaper, much faster, cooler and certainly easier to open up. Just ask for list of components for your need in any decent forum and get it assembled from a good shop. Prefer intel for cpu. i3 4th gen is enough for most use cases (even gaming upto 1920)