The usual process for getting a PC for me and my peers always has been this:
You start with the amount of money you want to spend. Then you make a list of parts you need, this is also where you decide if you need a screen, keyboard etc.
Then you look at your needs and prioritise your devices, i.e. for orbiter the graphics card has a pretty low priority.
Then you do research on technologies (aka AMD vs. Intel), check benchmarks for individual components. Look at recommended setups, like the ones TomsHardware does from time to time. (note: This does NOT mean look at prebuilt setups from stores!)
Once you did this, you will have a pretty good idea what system you want to build, you can now start fiddeling with different setups until you find one that gives you maximum performance for the money you want to spend.
A note on laptops: Laptops are only needed if you really work while on the move. And in those cases, you usaly only need a very very weak laptop. Something that will run your IDE, Office suite, email client. Even for orbiter addon developement on the move you don't need something powerfull, not even a GPU. Excessive test flights are done at home, in peace and not on the subway. Running in RGB emulation is sufficient for checking the modell and thruster positions.
My point is, use the money you safe when getting a desktop and get a cheap laptop, if you really need it.
Happy Orbiting!