Tickets for train to Girona from Barcelona - RENFE question
 

Got a question:
We want to take a day trip to Girona from Barcelona. We'd like to leave from the Passeig De Gracia station (only 2 blocks from our hotel).
The train we want to take is the 08:20 train that arrives in Girona at 09:36.
On the return route, we want to take the one that leaves Girona at 17:47. We want to ride this one to the Sants station where it should arrive at 19:09.
The issue with this is: how do we buy these tickets? Looks like there is no option to buy online. Can we only get these @ the station?
What's the best advice for getting these tickets? If they are only at the station, are we ok to buy on the day of? Or do we need to pick up a day earlier or so?
Thanks

Reservations are not needed for these trains. They are commuter trains and run every hour, with extra trains in the morning and evening. Most commuters will be travelling to Barcelona in the morning and to Girona in the evening, so the trains will not be so busy in the opposite direction.

So when I buy the tickets at the station, do I need to specify the return time. Or do I just buy the return tickets in girona whenever we are ready to head back to Sants?

Just got back from our Barcelona trip & did take the train to Girona , you buy the ticket at the station and you have to use it within the hour ( at least that's what they told us).in other words you buy it on your way back.. Girona is beautiful, enjoy!

we bought tickets both ways (ida y vuelta ); if I remember, no one checked the time either way.

Do you have to specify the return time when you but the ida y vuelta tickets at the station?