Corsa 1.2 Ecoflex Diesel

I have just bought my first caravan, a 1995 Compass reflection 2-berth. I matched my Corsa 1.2 Ecoflex Diesel (2009) against it and got green ticks but a warning yellow about possible sluggishness on hills and at junctions. Should I change my car before I have the quite expensive towbar and electrics added? We are heading off around Europe for a while and I don't want to discover I can't get up the approach roads to some of the campsites.