Welcome @jerrybracco.
I got two basses recently, one was brand new in the box, one was used from Guitar Center.
I had to do set ups on both of them, and both were opposite each other. After the initial set up I still had to dial them in a little, but it’s way worth it because they both have ultra low action and are in tune to the 12th fret harmonic. I have not spent time to do a thorough intonation on them, leaving them as good enuf for me for now.
My Ibanez SR300 (Used) had action a little higher then I wanted. The neck needed to be flattened a little bit by tightening the truss rod, only about 1/4 turn. Then I lowered the action, and it was great, the way I like it. The next day I changed the strings, put on some Black Beauty’s I ordered online. After the string replacement, I noticed a lot more buzzing around the frets on all strings that the old dead strings were not picking up.
I ended up raising the action slightly, 1/4 turn at the bridge at a time until the new strings rang true on every fret. Results are still great.
The brand new ESP LTD B4-E was the opposite.
The set up from the factory was almost perfect, and I assume it was stellar all the way around when it was purchased from Sam Ash. However, the seller bought it in 2017, and had it in a closet, on the original packaging / box until he sold it to me two days ago.
The action was ultra low, beautifully so, but there was terrible fret buzz, almost deadening the note from the 1st thru 5th fret on all strings.
I noticed this testing it out, and used the fact “I will need to have a set up on it” as a way to knock $80 off his asking price, which was already $250 lower then the $700 retail list price (verified on reverb, which has some 2013, 2016 and 2017 of the same model, new for that price, this one is 2017) .
When I held down the E string ar the 22nd fret, it was laying flat at the 12th fret, with no air gap. This was a case of the neck being too flat, and the truss needed to be loosened about 1/3 to 1/2 turn. After doing so, I had the proper air gap at the 12th fret, when pressing at the 1st and 22nd fret, but there was still string buzz, and the I played Brit’s nick.e round wound strings picks up every bit of it. I spent a bit of time raising each string at the bridge, ever so slightly, checking each string after every tiny adjustment until I got most of the buzz out. The round wound, un broken in strings will pick up some, but each time I play it, I find a fret here and there that had too much buzz, so out comes the hex wrench, and I again, make a slight adjustment until it is better. The action is still super low, I have not had to raise any string anywhere near being too high and in playable, so I, again, am very happy with the result.
Not only do I save money on a set up, that I am too inpatient to wait for a place to open where it could be done, but I really love the hands on, learning along the way, and the overall accomplished feeling I have for doing this on all of my Basses.
I a sure you can do the set up yourself as long as you have the few tools needed, and watch that video posted above, and another good one by the guy at guns and guitars, and you will yield the same satisfaction of fixing your buzzing string problem all on your own.
Of course, we are here to help however we can.