Nobody can really predict that, since it depends on your design. But, stab area (projected through the fuselage) of approximately 20% of the wing area (also projected through the fuselage) or larger, is a good start. Better to have a little too much than too little. If you want to go into the design process with a little more confidence, and don't want to read a lot of technical information, then simply collect images of many successful jets, compare them, and see what seems to work best. We all learn from our predecessors.

If your design allows the option, try and design it so that, without changing the fuselage, you can try different tail parts. Don't get locked in to a particular configuration before you've successfully flown the plane. (!)