Every week a Guardian Money reader submits a question, and it’s up to you to help him or her out – a selection of the best answers will appear in next Saturday’s paper.

We are buying a car seat for our newborn child. Should we buy a rigid Isofix system or are the car seats that attach via a seatbelt good enough?

Do you have a problem readers could solve? Email your suggestions to money@theguardian.com or write to us at Money, the Guardian, Kings Place, 90 York Way, London N1 9GU.