I did a "run-in" DIY oil change on my R - it was a complete doddle. If I remember rightly, the car took 5.6L of oil to the top of the checked markings of the dipstick, the oil filter was about £13 and the new plastic sump nut/plug was about £2.30. There are little green paint marks applied to the filter housing and housing base that line up to know you haven't overtightened it. Castrol Edge or Mobil 1 fully synthetic 0W40 or 5W40.
If your car is under warranty I would not recommend a DIY oil change in lieu of a proper service you'll be required to have proof of to maintain your warranty.