I am a UK VAT-registered LTD company renting out my own flat through a letting agent. They charge a 10% service fee and then add 20% as VAT. When I asked for a VAT invoice, their accountant refused to provide one and stated that no VAT applies to rent. To verify things myself, I used VATCalc.Onl to check what 20% VAT charging looks like. The tool helped me clearly understand how to add or remove VAT from the agent's fee so that I can confidently request correct billing or a refund.