Re: van stock ??
Get all your parts invoices together and they should give you some idea of your recent usage.
It really depends on the range of appliances and more important the size of your van. 🙂 Trying to give you all the part numbers would be a little difficult to say the least. For instance I carry one Hotpoint WM drum support with me and have another four at home. I can use three or four in a week then none for a week or so, however an engineer working in a hard water area would rarely use one, he may however use far more elements than I do.
To your short list I would add, door seals, pumps, door interlocks, bearing kits, drum supports, heaters, just for starters.
It really is all down to experience and proper stock control even if it is all done in your head ( like mine ) 😀
If I find I am constanly having to order the same part then as long as cost is not an issue I will start to carry it.
A regular stock taking should identify parts that you have to many of, or are not using as often.