Dunno the toll in France, but the N2 (N II) in Spain runs down from just South of the mountainous border crossing at La Jonquera to Barcelona and it’s free.
It also goes around Figueres where there’s a truckstop and all diesel card fuel pumps, cheap (I think). That’s near the major junction for Roses.
The N2 is slightly slower than the Auto Pista on a good day, not by much though and it can be a bit quicker.
You rejoin the AP ■■ just before Barcelona. You don’t want to be going through there on small roads when there’s a motorway option 
I haven’t been to Spain for over 10 years, so my knowledge is probably out of date now.
If it is, someone will put us right 