modifying ryanair booking adding baggage to check in
 

hi!
two days ago i booked a flight with ryanair with 0 bags to check in (only hand/cabin luggage) and i haven't done the online check in yet. i would like to know if it is possible to add a bag through the "manage your booking" link and still check in online paying just the additional fee for luggage (2x10 eur for a return flight + 2x2 eur of VAT= tot. 24 eur)? on the web page they state you have to go through airport check after adding luggage and pay the airport check in fee. how much is it?
thank you!

You can do this over the phone and they could answer your questions too....I still need to take care of this for myself.

Yes, it is possible to add bags, pay just the fee of €10, and check-in online. At least I did it that way 2 weeks ago, and had no problems with online check-in, and did not pay a fee at the airport.
There seem to be certain restrictions for online check-in on some routes (Morocco or somewhere, I guess), but Ryanair has switched to mandatory online check-in (again, maybe not for some few destinations) now anyway.