The potential issue with the C220d is that, like all MB cars fitted with the AdBlue system, they are prone to expensive AdBlue related faults. I would recommend considering a C200 petrol instead (with the M274 2.0L Turbo engine), or alternatively factor-in the cost of a warranty that covers also the AdBlue system for when the original seller's warranty expires.
Re FSH, I suggest that you ask the seller for an actual printout of the service history from the MB Digital Service Book (even if the seller is an MB dealer - soory but some of them just can't be trusted). Sadly, there have been cases where buyers were promised SFH, but then when they wanted the buy a service plan, they were told that some services or service items were missing and they'll have to pay for them outright before they can purchase a service plan.
I also suggest that you run the car's VIN in an online VIN decoder, it will tell you exactly which options have been fitted to the car from the factory. You can also post it here for some further advice if you like.
Then, the car will have one of two infotainment systems: either the entry-level Audio20 with the optional Garmin Map Pilot navigation on SD-Card, or the high-end COMAND NTG5*2 with the built-in navigation on an internal HDD. COMAND is the better system, and from memory was standard on the Premium Plus model. The COMAND unit also has a larger screen.
It might be worth checking with the seller that the car comes with the latest version of the Garmin Map Pilot SD-Card (if Audio20), or that it has the latest maps uploaded to the HDD (if COMAND). And, if the seller is an MB dealer, I would also ask that they update the firmware on the infotainment system to the latest version (this is a separate update to the maps, and it's free).
Also, note that neither the Audio20 nor the COMAND unit have native support for Apple CarPlay or Android Auto, though it can be added using additional (non-MB) hardware at a cost of £300-600 (varies based on type of adapter and on installer). DAB was available as an option, and if the car doesn't have that then it can be retrofitted. And, cars equipped with COMAND also had the optional Burmester sound system, though in reality if you're an audiophile than none of the factory fitted audio options will be good enough and you'll probably want to replace the speakers anyway.
Sadly, these cars are fitted with the 3g modem and use the now-discontinued Vodafone 3g network, which means that the Connected Car services (including real time traffic for COMAND) are no longer working. Unfortunately there's no way around it, other than buying the facelift model (2018 onwards) that has the 4g modem, but even then it's not guaranteed that the services for older cars will be available for much longer.
By wary of Sport models with stiffened lowered suspension and optional large wheels, they look the part and the handling is good, but the ride is poor - a model with the basic 16" wheels will be your best best if you prefer smooth comfy ride over a crashy sporty one.
And last, there's a plethora of driver aid systems that were optional, such as adaptive cruise control, blind spot assist, lane keep assist, active parking assist, etc - might be worth checking what the car actually had and see if your happy with that.
Good luck!
I have owned only bmws in the past, can't afford the new 3 series and I have already owned a 2015 1 series and a 2016 x3 ( the interior is identical).
