They are almost always scams.
Since this is a mod, make sure to mention if you have a specific installation guide or if they need a "No-OBB" version, as Android users often look for the easiest setup! Which platform are you planning to post this on? I can tweak the tone gta underground mod android
that aims to unite the maps of multiple Rockstar titles—including (Liberty City), GTA: Vice City (Carcer City), and They are almost always scams