Is it CPO? Make sure the latest service was done at the dealer (usually right around 45-50k), that should take care of the common issues. Depending on how the car was driven previously, they may or may not have done the brakes. You may want to inquire specifically to see what's been taken care of already.
'15 i3 REX // Capparis // ZGW // ZTD // HK // 20"
20% Tint, Coding, LED High Beams/Signals, Painted Reflectors, MAX2 Hardwire
Past: F30 335i, E90 328xi