We are talking about money, so this is the term I would use

Il corrispettivo è ciò che viene corrisposto al
The payment is what is paid to somebody for something / in return for simething
The price is what is paid to somebody for something / in return for simething
The valuable considerationis what is paid to somebody for something / in return for simething

I often translate this word many times each day. There is no one translation

l’importo versato a corrispettivo dell’opzione (originaria) verrà imputato in
the amount paid in return for the option
the amount paid for the option
the amount paid as valuable consideration for the option

will be recognised in the account for the sale of the ..... i.e. it is accounted for in exactly the same way as the sale of the rights for the use...

I have just translated the word myself here, I used "outlay" because it goes with cash:
Il corrispettivo a pronti dell’operazione è stato di 120 milioni di euro, con una componente aggiuntiva dilazionata nel tempo (attraverso un meccanismo di earn-out legato al raggiungimento di determinati volumi di premi) pari ad un valore attuale di circa 40 milioni per una valutazione complessiva di xxx di circa 320 milioni di euro.

The cash outlay for the transaction was 120 million euro, with a further amount to be paid in instalments (by means of an earn-out mechanism linked to the achievement of determined volumes of premiums) with a present value of €40 million, to give a total value for xxx of approximately €320 million .