Well, buying a crappy instrument will make a difference to the negative.
The question I’d have is “Is the instrument itself crap” (warped neck, incorrectly set up, dirty controls) or is the brand crap.
For a beginner, there’s no such thing as a crap brand - you need to play for a while, get a sense of your style, of what you want out of an instrument before you can really figure out what constitutes “good” for you. There are a bunch of great instruments that I can’t stand, because they are totally unsuited to my style.
As for a bad instrument, you’re kinda at the mercy of the person who sells it to you. You want a reputable place where the guys in the guitar center are good at fixing or setting up instruments. To find one, you might go to a local band at a bar and ask the bassists/guitarists where they go for repairs/purchases. It may sound judgemental, but the better the guitarist and the better their instrument, the more you can trust what they say.
Whatever you buy, take it and have the guy look at it and give you their assessment.
A general checklist:
Check all hardware: is anything loose? Especially check the jack (where the cord connects)
Plug the instrument in, and work all the controls - turn the knobs, flick the switches - do you hear any gritty sounds coming out of the amplifier? the controls are dirty and need to be cleaned.
Pluck something steady and start playing with the controls. Ask the person who’s selling you the instrument to walk you through what the controls should do - there are some basic setups, but who knows on the bass you’re looking at.
As for Setup, intonation, and neck warpage, it’d be best if someone else look at that.
Setup has to do with how high the strings are off the fingerboard and it affects playability.
Intonation has to do with whether the string length is correct (adjusted at the bridge) so that notes stay in tune the higher up the neck you play. the quick test (for a beginner) would be to play the open string, and then place your finger on the 12th fret (the one halfway up the fingerboard, typically with two dots) and see if that note is an exact octave (higher, but still in tune).
Warpage is a big nasty that can affect poorly made instruments, or instruments that have been subjected to a lot of abuse. Essentially speaking, there should be no twist to the neck (looking down the fingerboard from the headstock to the bridge), and there should only be a very slight, even forward bow when you look at the neck from the side.
Basically, if you buy a new instrument from a chain, then you run little risk. . .
If you buy a used instrument from anywhere, be sure to have someone experienced assess the instrument.