Hi Mike,
You may not get a satisfactory answer. Production, trim and specification differences mean that you can see a 100 kg or more variation between identically engined models.
But at least the printed kerb-weight should be the lightest possible weight for a basic specification car, fuelled and ballasted as per the small print - but if you have plans to buy a model with more options - not least 25 to 40 kg of tow-bar - then it will always be an underestimate.
Robert