the_traveler
Engineer
As said, you can upgrade at anytime - if the roomettes are available.We have already purchased our tickets for coach. Could they ever be upgraded to sleepertte?
If the tickets have not yet been printed (and I recommend you do not until you get to the station that day), it is very easy, as you can make your roomette reservations and then cancel your coach reservations. If they were printed, it's a little more work, as you can get the roomettes (if available), but you have to go to the station to get them re-ticketed. The old tickets can be used to apply 100% of the value of those (old) tickets to the cost of the new tickets.
As an additional thought about upgrading, tickets on Amtrak are sold by "buckets". That is the more tickets are sold, the buckets rise (in price). Thus sometimes (not always) the coach seats may be high bucket and the roomettes low bucket - and the roomettes are actually less than coach!
And when you see the accommodation (room) charge, note that is PER ROOM, not per person!
Another think is I would recommend ALL of you to join Amtrak Guest Rewards (AGR) prior to your trip! AGR is similar to an airlines frequent flyer program, granting you FREE travel. I assume you live in or around LA. There are many trips you can take for only 1,000 AGR points around CA by train! Just this one trip will provide you many of those trips!
If you would like a referral to join AGR, just send me a PM (Private Message) with you email addresses. (Each account needs a separate email address.)
One more thing - buy your tickets ASAP! As long as sleeper tickets are cancelled at least 7 days prior to departure, or coach tickets at any time prior to departure, there is NO penalty!