Key features for us need to be
size - not massive as needs to fit on the worktop
energy efficiency - saw a lovely one and then realised it was rated E
price - no more than £100
colour - preferably not black/silver/white but if that's what I have to take then I will.
To be honest, we mostly use ours for cooking peas, heating soup, beans etc and randomly making scrambled eggs. Have a perfectly adequate cooker/grill so not really needing it to be an all singing/dancing microwave.
Thanks.