I have just received my company number and now want to sell things I created before I had a company number.
In other words, I would be selling items I created with materials I purchased as a private person.
Is this allowed and how should I go about it?
First, you need to enter those materials or products in your accounts. You will then have to buy those items from yourself as a private person. There is a useful article about this in the learning center, which provides an explanation of what you need to do with purchases made before you became self-employed: https://dexxter.be/kan-ik-purchases-inbrengen-from-voor-de-opstart-als-zelfstandige/
You really should try it out for yourself. Even if you don’t have a company number yet, you can already go ahead.
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