Our international flight from USA lands in Rome, FCO, at 8:10 AM. We would like to take the Italotreno to Salerno which leaves Roma Termini at 10:23 AM. Do we have time to get through customs, etc, get to Termini to take that train? Also, is there a car rental company at the Salerno train station? Grazie
Absolutely not. The big variable is immigration in Rome. Could take 30 minutes, could take 2 hours. And then you need to plan an hour from the airport to Termini just in case you just miss the Leonardo Express that runs every 30 minutes. Even if you could sail through immigration it is still too tight. The best advice is not to book your train till you see the white of the eye of ticket seller at the airport.
And on the plus side, good old Google Maps shows a Hertz agency at about fifty metres from the Salerno railway station.
That is not enough time to safely get a 10:23 train from Termini. If your plane arrives at the gate on time, I would allow at least one hour to deplane (how I hate that term) clear customs and immigration and get to the rail station, assuming you only have carry on luggage. Now you've got to get a ticket, wait for the next train and go to Termini. Then, it's time to disembark and transfer to the Salerno train if you've already purchased your tickets.
Since you'll be renting a car, consider picking it up at FCO instead of taking the train. Going by train involves changing in Rome and then again in Naples. The convenience may well be worth it.
I agree, it's unlikely that you would make that train. Good suggestion to just rent the car at FCO, you can avoid all city traffic.