This is a variant of the realtor commission calculator which also adds value added tax to the commission (but only to the commission, we assume that the house price is not a subject to VAT). Also, it appears that in most cases the commission is only taken from the selling party. I know there are exceptions and if you’d like such (or any other) case to be covered, we’ll happily build a calculator for you. Just contact us.
An example situation: a realtor is an intermediary in a transaction. The house sells for €100000. Realtor’s commission is 3% and a 23% VAT rate applies. The net commission is €3000, which becomes €3000 + €3000 * 0.23 = €3690 gross. So the total owner of the house receives €100000 - €3690 = €96310.
You may also want to check out the regular commission calculator.