Company needs to register a predominant activity, in process of company registration. Both DOO and individual entrepreneur can perform all activities that are not prohibited by law, but if you are flat rate taxated enterpreneur (preduzetnik pausalac), you can only perform activities which are allowed for flat rate taxated enterpreneurs.
Here you can find classification of activities in Serbia.
Here you can see which activities can not be performed by flat-rate taxed entrepreneur (preduzetnik pausalac).
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