@Nicola ***********
you don't need agency you can do it yourself.
My girlfriend dont have a job neither and came 4 times in France.
Apply for a tourist visa (i recommand to ask only for 3 weeks - 1 month for the first time).
Book a flight with return. (You can book it on "book for visa. com" for 15$.
Book an hotel reservation.
Get a schengen inssurance.
Put 200k bahts on her bank account.
And that's it.