Where do you buy your parts?

[Tove22]

Where do you guys buy your parts? I own 2 BMW's (one is a 2007 335i and the other is a 2016 X5 M), do all of the maintenance myself including replacing parts. I usually buy online because the prices are cheaper but have used the dealer before when time was a factor.

What are your go-to part sites? My favorite (usually because of the prices and service) are http://www.realoem.com and https://www.bmwdiscountparts.com, but maybe you guys have found better choices.

Also, does anybody have experience with a dealer willing to install legit BMW parts that were purchased online? There have been several times when I started a repair and half way through realized that it was going to take way more time than estimated. In both of these instances, I would've rather just paid a dealer/independent BMW mechanic to finish the repair.