An update, I went with Iryo for my Barcelona to Seville ticket and it costed similar to their second class ticket so I went with first class. I tried to book Seville to Madrid ticket last night with Renfe AVE first class since I thought I could try both Iryo and AVE.
Horrible experience, I used PayPal because I read about issues with foreign credit cards and it said issue with transaction, I tried a second time and same issue, since I had my credit card email notifications on for online purchases, my bank sent me two emails about the transactions. Even though I received no email confirmation from RENFE nor could I find it in my PayPal Activities. I called RENFE customer service and they said they cannot find my reservation since I did not have PayPal transaction ID and when I gave my passport number the agent also couldn't find it. Agent suggested I just input my credit card as normal, which I thought was confusing since the website has interest free loan payment in four option. She said I could however just choose credit card and it will allow me to pick just pay in one option.
I did not book last night as I wanted to be sure I will not be triple charged as I can see the seats I chose in my two failed PayPal purchases shown as being reserved. Well today came and prices went up perhaps because the system thought my failed PayPal purchases went through and raised the price due to increased demand. In a fit of anger I just went with Iryo Singular with six euro add on for luggage and changing seats. This after I took the trouble to register for RENFE. Can they not update their system to work with foreign cards either with PayPal or credit card itself?