Window regulator is not a big deal as it seems and like was said - it could be just a plastic pieces. I just did mine last week - it is less then an hour job (plastic holders) may be a little longer for whole regulator because there are more screws, you'd have to remove more of that soundproofing material and removing/inserting a window regulator itself seems like top-notch acrobatic exercise but there plenty of guidance clips on YouTube.
-oil and filter change - this is done with every oil change so if your car is due for that - go for it.
-fuel filter kinda pain to do, It was a disappointment for me to see where BMW engineers shoveled that filter to, it is DIY doable but seeing it's done by mechanic first will helps with next time (it is almost $100 part, so you know)
-air filter - few min procedure
-pollen filter 10 min procedure (if you have a vacuum cleaner to clean the surrounding area, that would be awesome)
-spark plugs - 50/50, I took it to mechanic, I guess I just did not feel like grabbing the wrench it on that particular day (having magnetic socket and torque wrench is recommended)
-differential fluid change (and Transfer case) as well, easy if you can get the car high enough AND SECURE to be under it - relatively easy, all 3 can be changed in about 1.5 hrs, simple pump that inserts in to the oil bottle and tools to open fill/drain caps is all you need ...
Should you decide to go with mechanic, please make sure that they use proper oils.
I went with OEM BMW in differentials and Liquid Molly Synthetic for transfer case, I can text you a pictures of bottles if you PM me your cell.

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2009 Range Rover Sport SC HST Limited Edition
2014 Infiniti Q50 AWD