How much does money (or any desired good) influence a person on average?
Here are two studies may be relevant to your question:

Seeing green: Mere exposure to money triggers a business decision frame and unethical outcomes. The authors report that &quot;individuals primed with money were more likely to demonstrate unethical intentions than those in the control group&quot; and &quot;money cues triggered a business decision frame, which led to a greater likelihood of unethical intentions and behavior.&quot; This article explains that the researchers &quot;primed&quot; the participants by showing them either &quot;money-related&quot; phrases or &quot;neutral&quot; phrases and measured how that affected their decisions in hypothetical scenarios or games. So even when there is no actual money involved, the study found that thinking about money can influence people's behavior.

Social Class, Contextualism, and Empathic Accuracy. The authors report that &quot;individuals of a lower social class are more empathically accurate in judging the emotions of other people.&quot; In this article, a study co-author points out that people with more modest financial resources need to depend on others more than people who are more able to solve their problems with money. This may give them more experience cooperating with people and developing empathy. So in this case it's the money that someone accumulates throughout their life that may prompt them to act in a less empathetic way.