I would use a bathroom scale and piece of wood to get an accurate nose weight then use a spring scale and mark nose weight on it
spring scale came with me and used as a quick check if i had changed anything whilst away from home however caravan packing stayed the same for about 24 years
I check my nose weight regularly. Can't do it at home but do it before I leave site. In general it's within a few kg of what I'm looking for. I think it's one of these things that you become familiar with, as 90% of the time you are taking the same stuff with you and will Always pack things away in the same place.
Just make sure your van is nose heavy but within the weight limits for your tow car.
When I use the caravan its either for wife and myself or both of us plus daughter and grandchildren. I take the same stuff each time depending on whose going the only difference is in the loading of the car and positioning in the caravan. I check my noseweights for caravan and towbar once per year to remind myself of positioning items in caravan. One of the problems of having an Avondale is its useless front locker - small and not waterproof. If there was any material change in items being carried I would recheck.
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