Your warning is well said. I would go a step further and say that anything we read, other than scripture, SHOULD be taken as opinion only... the same as when we study together. Learning is a process, and it involves hearing other (sometimes contrary) viewpoints. That's why it is of utmost importance to pray for the Spirit to guide you and give you understanding in your study. The commentaries are just a good "jumping off point"... but many times they provide good, historical background which would be difficult to find simply by reading the scripture.
I took a class and they had me counting every word in the verses I was studying. They made it painful because they really didn't want me to study the Bible.
I usually use dictionaries to look up the Greek or Hebrew meaning of every word. I use online dictionaries because they are faster. I have printed dictionaries as well. Also, there are some meanings in Hebrew that some dictionaries won't help you figure out.
On top of that, I use half a dozen commentaries but they are always to be a last resort because the rule is to let scripture say what it says. I also use the commentaries on biblehub.com and look at the different ways different translations translate a word. I also have different apologetic books and reference books where different scholars write about an issue.
There are online resources as well. There are pastors who have MP3's on every chapter of the Bible and they've been teaching a long time.
I also write about a topic when I learn about it and it serves a purpose when I learn more and can add to what I write so I have second generation and third generation Bible studies.
When I look things up, I ask "What does this mean?" and not just "What does it say?" because you can get different results. I also do word analysis and look for context.
I pray about it and leave and then God sometimes gives me verses to think about.
I put the end result of going verse by verse into my systematic theology.
I get a lot of opposition in studying the Bible and the majority of people don't believe God because they view the Bible as just a historical book and not "God breathed" so they will always say what I write is "out of context". My apologetic and hermeneutic is that all scripture is God breathed and useful for teaching, etc., and the Bible was written for our example:
2 Timothy 3:16 All scripture is given by inspiration of God, and is profitable for doctrine, for reproof, for correction, for instruction in righteousness:
In other words, they want to say the New Testament is out of context because it is a historical book to them and shouldn't be profitable for doctrine, for reproof, for correction or instruction because they don't believe it is scripture and I can prove it is scripture because they don't know their Bibles and I am an adult Christian who can win this debate.
1 Corinthians 10:11 These things happened to them as examples and were written down as warnings for us, on whom the culmination of the ages has come.
These things were written for our "ensample" or "example". The words mean the same thing. The person that doesn't believe in God's word will say, "out of context" because it isn't a living breathing book to them. They are unsaved and don't know God because of how they act basically. They might believe in God but they aren't following God because they don't know Him, trust Him or make God the Lord or King of their life.
Bible study is not just reading the notes in your study Bible when you come to Bible study. Bible study begins when you know what you will be studying before you come to Bible study. Bible study takes years of preparation.