Private: someone selling a home they own, which covers most purchases. Builder: a new home sold by the company that built it, usually within five years of completion, with VAT instead of registration tax.

Lower taxes, known as prima casa, if you move your official residence to that town within 18 months of buying, do not already own a home there, and have not used the same relief on another Italian home you still own. Selling within five years without buying again can mean paying the difference back.

Properties filed as A/1, A/8 or A/9 in the land register: grand apartments, villas, castles. They cannot use the main-home relief, and from a builder they carry 22% VAT. Most homes are A/2, A/3 or A/7, so leave this off unless you have been told otherwise.

The cadastral income, a figure on the visura catastale that the agency or the seller can give you. Private buyers usually pay registration tax on a value worked out from it, which is much lower than the price. Leave it blank if you do not have it yet, and the app estimates the tax from the price instead.

In Italy the agency that lists the house normally charges the buyer as well as the seller, usually 3% of the price, plus VAT. Ask for the figure before you make an offer. Set it to 0 if you are buying without an agency.