We hired from Italy Car Rent through Ryan Air. It was the most hassle free pickup and return of a hire car I’ve ever had. They made no attempt to sell upgrades or additional insurance. They just put a hold on my credit card for the €900 excess. Quick check for damage on return and we were done.
They are a short walk from the terminal (don’t bother waiting for the shuttle bus).
We will book with them direct next time as it will be a little cheaper.