If I was to buy a Windows 10 laptop and started to make partitions to install different operative systems, what problems should I expect? Are there any good sites/guides where I could read about the subject? Thanks in advance.

Hm. Well, Microsoft has an official for dual-booting Win10, but since it's Microsoft, it only tells you how to dual-boot with other versions of Windows. I've usually found [url=http://www.pcworld.com/article/2955460/operating-systems/dual-booting-linux-with-windows-what-you-need-to-know.html]PCWorld to be at least mostly reliable, and that article is about dual booting Windows and linux.

I would say just Google the specific O/S combination(s) you want.

I dual boot it with Ubuntu 14.04. No issues so far.

I forgot about it, but I'm able to dual boot Windows 10 with Linux Mint and SolydX (or SolydK). You just need to disable and reenable safe boot or something, I don't really remember.

when dual-booting into windows 7 from 10 it does a restart and enables option for windows 7. That is the only thing I notice but I only tinker with linux in a VM.

Works well. I dual boot between Win 10 and OSX 10.11.5. Originally using Legacy Booting for Win 10, after upgrading from Win 7. I converted the drive to use UEFI instead of Legacy, and OSX now boots with Clover for UEFI.

(Had a little problem initially as my ASUS MOBO was having a fit with a mixed boot system, after a bunch of reboots the list of devices to choose from kept incorrectly increasing to the point that it would stop on the bios screen until I removed all but one disk, rebooted and then reconnected all the drives)

Be aware that there is a feature called "fast startup" that causes the system to actually hibernate when you shut it down, in order to make the next boot faster. Unfortunately, this also means that if you boot into another operating system (Linux) and then try to access the partition, it could easily cause data corruption.

Fortunately, it is possible to disable this feature, and if you're dual booting, you should. (While you're at it, you might consider removing the Hibernate button from power settings if it's enabled.)