There is a significant agreement between most denominations, e.g. salvation is through Christ (the Son of God) who died and rose again, God is Creator, sin is the main point of emnity between God and humanity, etc. And, of course, lots of disagreement.
I agree with those that have pointed out the "biblical authority" that leads to denominational differences is ultimately a matter of interpretation. In other words, it's a matter of human error, which is to be expected. What follows from that? Any claim that my interpretation is correct and another's incorrect is ultimately an appeal to human authority. Of course, that's not the conclusion anyone wants. Each wants to say theirs is correct.
If the scriptures have any authority at all for Christians, it must be rooted in the risen Christ. It cannot be that scriptures are self-authenticating. They have authority, if and only if, the one proclaimed within them actually came, died, and rose again. He is not risen because the scriptures say so. They say so, because he is risen.
People try to ground the authority of scripture in its own perfection, its inerrancy. That's a fool's errand. It doesn't have that function. It is a means that points to an end. Only the incarnated, crucified, resurrected, ascended Christ can ground the proclamation found within the scriptures. Whether the scriptures, as a whole, are perfect is irrelevant. The witness doesn't have to be perfect to speak truly about the perfect One.
If the scriptures were perfect and self authenticating, we wouldn't need the witness of the Holy Spirit. To say the Holy Spirit helps us see the scriptures are perfect is redundant. The Holy Spirit first helps us see the truth about Christ as proclaimed in the scriptures. Once that happens, the perfection of the biblical witness is irrelevant.