Being an entrepreneur in the Netherlands and you perform a job that is related to commercial real estate, such as maintenance or innovation, then the invoice send is subject to Dutch VAT. If the client lives abroad and asks you to send an invoice at 0% VAT for the work done to the real estate, then you cannot comply with the request. The real estate is situated in the Netherlands, hence the job was done in the Netherlands, therefore Dutch VAT of 21% will be due.
The lower, 6%, VAT percentage, that is referred to as a crisis measure only applies to homes, not being commercial property.
If you are an EU company not having a presence in the Netherlands, performing services related to commercial real estate and you use Dutch subcontractors for the job, then the sub contractors also invoice at 21% to the EU VAT entrepreneur. The 0% VAT rate does not apply, as the place of the work done is in the Netherlands where the real estate is situated.
When you provide services in the Netherlands related to the maintenance of commercial real estate, you are an entrepreneur for VAT purposes in the Netherlands. That implies that foreign companies performing such services in the Netherlands are obliged to file a VAT return as a non resident entrepreneur. The VAT return for these entrepreneurs is done slightly different than the regular online VAT filing.