We have recently sold our house in Italy and bought another (on the same day which I gather is unusual). Although my Italian is serviceable the Notary insisted on a translator and organised someone to translate the contracts and attend the two sessions when they were signed. Fair enough, but I was staggered to find that the charges for translation came to 1350 euro plus IVA. We had no opportunity to choose our own translator or review the fees, which strike me as grossly excessive given the amount of work involved for bog standard property contracts. Do others agree, and if so is there realistically anything that can now be done? I suspect some kind of stitch up but I also suspect that we may just have to grin and bear it

Are they charging both parties (if either your buyer, or the person you bought from also needed a translator)? Or is this just for the purchase?

The person we sold to had given power of attorney to a fluent Italian speaker, and the people we bought from are themselves italians. So it was just us who were charged fees: both for the sale and for the purchase

I would have changed notaries. Usually now nobody translates the atto itself because it can run to many pages. Much easier and cheaper is to do a POA to a3rd party who then signs on your behalf. A POA such as that in English and Italian will have translation fees of up tot 200 euros. If you can get it done in,say, London by a bilingual lawyer it will cost around 400 GBP with the legalisation fees. A notary here will charge around 350 euros for the POA itself.
I think 1300 euros to translate 2 atti is extortionate and the notary is running a little side line. He can insist on a registered court translator but the law doesnt actually require that. You should have had a) an estimate of cost and b) the chance to provide your own translator. I would have told him where to put it.

Where I live there are around 100 lawyers on the main street. Wealthy foreigners are fair game.

Have you got the name of the translator or the agency used? You could ask for a copy of the invoice. It would be interesting to see if there is an invoice or if the notaio just made up some figure to charge you? And if there isn't an invoice, how did the translator get paid? A notaio has to provide a clear and transparent estimate and has to list indiviual cost item separately. Even if you think there's no chance of gettig any money back, you could still write a strongly worded letter and hint that you're going to take the matter to the Cnsiglio Notarile.

The notary can insist on a translator inscribed in the albo of translators but cannot insist on a particular one. That is your choice.