Train question - getting on at a different station

Shauna,

As you haven't bought the tickets yet, you could probably save some money by purchasing the ticket for the night train from Verona to Paris, and use a locally purchased P-P ticket from Venice to Verona.

Difficult to tell. The conductor could consider your absence leaving Venice as a no-show and possibly reassign your place to another traveller. As the night train is run by Thello, not by Trenitalia, it is even difficult to be sure which regulations apply.

I wouldn't be particularly surprised if when boarding at Verona I found somebody who wasn't me in the compartment.

Both the conductor who probably has resold a no-show space and the person who isn't you who was told by the conductor they could move to that space would be shocked to see you trying to reclaim your space at Verona. I will readily acknowledge that I don't know for sure, but my money would be on you not getting your space.

Far better to buy your space for where you will use it. If you don't want to board until Verona, then buy for Verona and your space will be there when you get on.

On the other hand, if you are sharing a couchette with strangers from Venice, if you are on from the beginning you can negotiate bunk position with people joining at the same time as you. If you don't get on until later all the negotiation will have happened before you join and you will get the leftover.

Don't count on getting much if any sleep on the night train...

Do you already have your Thello tickets? If so, I would contact Thello directly by email now ask them specifically. There is no price difference between Venice SL or Verona for the train to Paris.
There is an hourly Regionale Veloce to Verona, takes 1 hour 17 minutes (from Venice SL, a few minutes less from Mestre), and costs 8.55 euro 2nd cl or 12.85 1st cl. You can buy these on your travel day as there are no advance discounts on regional trains.

Thanks everyone for your responses. I think it would be safest to book for Verona to Paris just in case I decide to go to Verona for a half day.

As for sleeping on the train, I'm not expecting luxury, but I am expecting a bit better than the night train I took through the north of Thailand!

It can't be as bad as the one I saw Anthony Bourdain do on TV the other night, Yangon to Bagan, Burma.