How Much Surface Noise is Too Much?

Just curious as to a range of opinions here. At what point is an LP unworthy of being played with your stylus/cartridge? Should one expect a used record store to give refunds on LPs which turn out to have more than a certain amount of surface noise/warpage and, if so, how much damage/defect should be criteria for getting one's money back? Any other thoughts along this line?
Everyone's tolerance level for surface noise differs, let alone the difficulty of quantifying surface noise, so it's really an impossible question to answer, IMO.

If you hear too much surface noise, then it's too much surface noise. However, I wouldn't count on the record store refunding your money for a used LP.
I'll put up with more noise if the record is a hard one to find or if the underlying sound is especially good but Tvad is right, everyone's tolerance differs. Digital sensitized many to this more I think. The longer you play vinyl, the less a little noise seems to bother.
When it interferes with your listening pleasure.
I'm surmising that styli/cartridges are pretty tough versus most run-of-the-mill record surface issues from an old brochure on the Linn LP-12 I remember reading ages and ages ago which said something to the effect of "even your battle scarred old discs will take on a new life...", but is there a point at which most of you reject the idea of playing a record out of fear of damaging equipment? How bad does a scratch have to be from this standpoint to relegate the LP to the rubbish bin?
I agree with Tvad, that you probably won't be getting a refund on a used record. I am sure the record store's response will be, "Hey, why didn't you inspect it before you bought it?".

(Even getting a refund on a brand new sealed record is no sure thing anymore. I've had more than one record store balk at refunding me money on obviously damaged vinyl.)

Good Luck!
Most people have their VTA set incorrectly. When it is properly set, the surface noise of an LP will be presented in a different plane from the music. Our sensory gating mechanisms can deal with this much more easily and tolerance of these abberations becomes much greater.
I don't know which stores you are shopping at but where I live all the stores give some type of guarantee for defective new records. Usually this involves exchanging it for another copy. I took an LP back to one store this week and swapped it for the CD as the pressing was just unlistenable. As for used vinyl, most stores will give you at least an in-store credit.
"How Much Surface Noise is Too Much?"

Isn't that a Jeff Foxworthy routine? Heheh.
My turntable is almost as quiet as my CD player...if occasional scratches ...pops, tick's, etc. are discounted.
Let’s assume the OP knows what a quiet LP sounds like in his system, and
let’s also assume his analog rig is quiet and properly set-up before we start
making him feel inadequate without justification.
Play the record.

If you enjoy the music and groove, good.
If you hear the surface noise and you don't groove, you have a bad record.

I have a new, used Neil Young album with some pretty healthy ticks. They do not get in the way of the music.
That is a good record.
Ticks and POPS are (if the LP has been cleaned) usually visible before I even started. I inspect LPs carefully before I buy. If they have any visible scratches.. I pass.
If you hold an LP up to sunlight and angle it just right, you can see a shimmering, almost rainbow quality in the grooves, and any defect will become visible)
(I already threw away thousands of slightly scratched LPs when I moved)
The 6,000 I have now will suffice if I can't find ones worth buying.
The best place where I buy used (secret) I can return stuff for credit, for any reason (I do NOT abuse this). They try hard to NOT buy damaged vinyl. And if it has a scuff or whatever,(and they bought it because it is rare or in demand) they mark it down.
As for how much noise I will accept: I will not put up with a repeating tic for more than three tics, and only one like that per LP. 3 tics seems to be my limit. Surface noise from deeper scuffs (that grating sound) I will also tolerate for a few turns of the table, and only one such per LP. The vast majority of my LPs are quiet.. but being an old hand (since 1965, yeah, I am a really old bag.) at LPs, I can say I know what I want in LP playback.
Forgot to add: the clean looking LPs with the dreaded constant surface noise (cleaning often will not fix) are trash. please destroy them if they are not a rarity.
Elizabeth, I agree that the most annoying ones are the clean looking ones with constant noise, even after cleaning. Is there any way one can tell by looking at the grooves in sunlight whether this will be the case before buying?
"Forgot to add: the clean looking LPs with the dreaded constant surface noise (cleaning often will not fix) are trash. please destroy them if they are not a rarity."

Please do not do this! You may later find that you cleaning method was not sufficient and trashed many otherwise good (and irreplacebale) albums.
You also may find that a different stylus cut rides in a different part of the groove that is not damaged, ie Shibata, Geiger, Van Den Hul, Fine Line, vs. conical or elliptical.