Roofliner removal/Dashcam installation?

Just bought myself a used 2012 R350 (gas) and I'd like to install a dashcam myself. Anyone has tried this before and can give me some pointers would be greatly appreciated!
Alternately, does anyone in Toronto has a good place to recommend when it comes to:
1) Dashcam installation
2) Leatherette repair
3) Fixing the failed keyless Go unlock buttons (all 4 had died on me just a few days after I took delivery
)4) General maintenance
Many thanks

best regards,
BrianC
As for the keyless go. um I have similar issues.. but it moves around! it used to be the drivers door, now its rear left side... depends on weather. I suspect it is bad connections in the door.
Not loosing sleep on this.
FYI: there are 3 key fob sensors that triangulate the position of the key! Thats how it knows if you are inside or outside!

I used to own two R classes under my company's name and back then, I was single, the R was just to haul passengers and clients around.
Now that I'm Married, with Children, the first vehicle that came to mind is the R and nothing else! Despite it had faded out of production for the rest of the world (except for China), despite it's an 8 year old vehicle, I bought it without hesitation!
I wish MB would eventually bring something similar back (not an SUV please! My senior parents couldn't climb up that thing!), otherwise, once this W251 breaks down, I really won't know what to replace it with!
best regards,
BrianC
Tucked in wire above windshield, then there are rubber bits around all the trim at the edges. With a small wedge tool, you can pull this back and push your wires behind it. Power went down side of door and then hides under das with only a couple of inches exposed. The wire to the rear camera followed the trim at the roof line all the way back. Had to leave some extra wire to allow the rear hatch to open without pulling on the wire. Didn't have to remove a single piece of panel or trim.
Good luck!
KC
Tucked in wire above windshield, then there are rubber bits around all the trim at the edges. With a small wedge tool, you can pull this back and push your wires behind it. Power went down side of door and then hides under das with only a couple of inches exposed. The wire to the rear camera followed the trim at the roof line all the way back. Had to leave some extra wire to allow the rear hatch to open without pulling on the wire. Didn't have to remove a single piece of panel or trim.
Good luck!
KC
What do you guys plan on doing with it? Posting on youtube?
And yes, I'll get some pics and put them up here.






