To make it clear I have the chance to buy this 4 Albums but I am not sure at all, if this signatures are authentic - that is the reason I ask for your opinions - THX
I can give you an idea about the value of authentic KISS solo albums. The rarest one is Paul Stanley. If you ever find one, it should be around $500. The rest of them you can find for around $250 - 300, depending on the condition and whether they are original pressing or reissues.
About the authenticity of the ones you are showing, I will let others chime in.