Generally speaking, Spanish-made .25 ACP pistols are cheaply made and unreliable. If it's functional, it's a curiosity.
If it's in brand-new condition, it might be worth up to $200.00 to someone. In good-enough condition, it's worth $100.00 or less.
It's interesting that its maker also produced revolvers marked "Alfa" (the Spanish spelling of alpha). Thus, they made guns "from Alfa to Omega," or, in English, "from A to Z."