Q: Reprimanding (pejorative) Idiom, phrase or expression for when one wants to pay less (minuscule) and get maximum out of a deal (basically greediness) What is pejorative phrase, idiom for 
one wants to pay less (minuscule) and get maximum out of a deal (basically greediness).
Example
The management wants to get talented employee but hire employees at 1/4 of their actual market value (for peanuts). They are __________ (min. input and max. output). This is not how it works.

A: One British expression is "They want to have a Rolls Royce and pay for a Mini" referring, of course to the cars. Note that this is 1960s/70s in origin so the Mini is the old 850 Mini which was about as basic as it got, not the current, much larger and more sohpisticated one.

A: They're trying to get more than they're paying for.
It's a literal expression, and is a variation on "you get what you pay for". Its connotation is slightly negative, and it just means that they're trying to underpay.
Here are some examples:

You've found your dream job on one of the job boards, or maybe even on the career site of what you think could be your dream company. Uh-oh. The title of the job doesn't seem to match the responsibilities and expectations. Are they trying to get more than they can pay for? Or, the job description is far too brief.
Toxic Interview Culture



Freelancing is hard. We spend half our days selling ourselves and our ideas, the other half chasing clients for payment  — then sleepless nights worrying about when we're going to get the actual work done. Clients are forever trying to get more than they paid for.
Attention, freeloaders: That coffee shop is not your office



I was accused by the thick, darker skinned african-american gentleman of trying to get more than I paid for, saying OH, you only ordered a Medium but you want the rest when you didn't get a Large?? 
When another employee went to remake it (which had way too much of the syrupy/sugary strawberries they used), I explained I ordered and paid for a Large, and not the Medium I was given, and the accusatory gentleman just stepped away with no manners to correct himself, just a smirk on his face, didn't even acknowledge that he accused a customer who paid for a Large of trying to get more than was paid for.
Yelp: Smoothie King


A: I'd use the term exploit: 

  
*
  
*If you say that someone is exploiting you, you think that they are treating you unfairly by using your work or ideas and giving you very little in return.
  

Collins Dictionary

They are trying to exploit new employees/workers

From linkedin.com

Over Exploitation of Employee: A Major Problem of Working Environment

