Can anyone recommend really good weighing scales I can weigh my dogs on?

[musicposy]

Bear with me, I know it's an odd question!

We have 4 dogs. Two are rescues, one of which came to us quite overweight and the other slightly underweight. One of the others is well over 12 and his weight tends to fluctuate very quickly if I don't watch it.

Therefore, once a fortnight I weigh all four (weighing myself first then picking the dogs up and deducting my weight), keep a record of their weights and adjust their food slightly if necessary (obsessive, moi?).

I have digital scales and they are crap. I can get on 5 times in a row and every time will be a different weight. I've looked for new, but looking at the digital on amazon, all have a large quantity of reviews saying they do the same as mine.

I looked at a salter mechanical but because they weigh right up to 150kg the weight increments are only 0.5kg which is not accurate enough to monitor the weight of a 6.5kg dog.

Is anyone else mad enough to do this and what do you use?