If you buy something for $1.50, in your experience, what kind of vendor will say, “That’s a buck fifty,” as opposed to “That’s a dollar fifty,” (or as opposed to “one dollar and fifty cents”)? At which vendors would it seem too informal for you, and at which places would it seem acceptable?
Consider places such as supermarkets, department stores (Macy’s, for example), liquor stores, street vendors, etc. (Cashiers formally trained at big retailers: What do they tell you to say?)
Thanks all!
Formal training?
I don’t know. It’s never occurred to me that the formality of cash exchanges was something to think about.
I think you may be reading (way) too much into this.
Either of the above is fine.
I’d just as often hear it as “One fitty” and care nary a wit.
It’s all good.
I don’t recall hearing a buck fitty from vendors. I’d be slightly more likely to hear “One fifty” rather than “a dollar fifty”.
Buck Fitty is swap meet lingo
I think “a buck fifty” is metric.
I’d think that any place that actually has something for sale for only $1.50, and presumably with tax built in to get such a round number, is automatically not some luxe place that cares about formality or informality. It’s pretty much only street stands, cheap cornerstores, and hole in the wall pizzerias that could come up with such a number. They could say nothing at all while sticking out their hand and I’d consider it par for the course.
12 bits.
buck fifty would be rummage/yard sale or swap meet.
Oh, 'bout tree fiddy.
If the item is a buck-fifty and you give them tree fiddy you should get a dollar three-eighty four in change.
Sounds about right.
Of course they’re both fine. The question has nothing to do with being “correct.” Reread the OP.
Yes, I realize that perhaps even more places will say, “One fifty.” Again, that’s not the point. I’m simply trying to survey what kinds of shopping contexts a person will typically hear the word buck used instead of dollar.
Well, you did use the word “acceptable.”
Now, addressing your survey, I am not sure I’ve trained my ear to notice the difference. I think I translate either word to “dollar.” maybe garage sales and fishing tackle shops say "Buck,"while lawn mower repair outlets say “dollar.” Of course, even those rules tend to vary by region and season.
I concur with flea market type places.
“A buck” something rolls off the tongue better than other uses - so I don’t suspect you’ll run into it at Tiffany’s as much “that will be 6,000 bucks” isn’t as cool as “6k” or “6 grand” for example.
I have worked at a very high end retailer - think not quite as high end as Tiffany’s, but in the ballpark. We never received any training on the use of slang (nor did we carry anything that cost a buck anything). Never the less - I doubt any customer would have cared if I said “a buck fifty” is your change. And I don’t think my manager would have ever said “we at Snob Emporium don’t use the term ‘buck’”
It is almost a tongue and cheek kind of slang. I picture it being said by an older white male hardware store owner. I don’t think it is as much tied to education as some other slang words would be. I picture it as sort of a friendly type of slang - I wouldn’t use it with a customer who had just chewed me out, for example.
I also think of it more like a male word - and more man to man than anything.
I’d expect to hear “a buck fifty” at my local hardware store when buying an assortment of nuts/bolts etc. The older guy that’s worked there since forever would probably be more informal than the guy behind the counter at a news stand.
But either one is acceptable; I find it odd that you think it would be considered “too informal”. Now, if Jeeves said it that way while helping me with my tophat and tails, I’d upbraid him for his insolence.
The nerve.
Around here, it’d be “buck 'naff”. 
As a cashier for a large retail chain store, I always say “one dollar and fifty cents”. I feel this is easier to say for one big reason, I deal with many elderly people and people with hearing disabilities and pronouncing each word helps if people are trying to read lips. I’m sure “a buck fifty” would work, but it’s a force of habit for me to say “X dollars and Y cents”.
I believe that staff at the high-end stores are more likely to say something along the lines of “one hundred and fifty dollars”. 
And just what’s wrong with “a hundred and fifty cents”?