From the very beginning of Pride and Prejudice we can perceive a preoccupation with economics with the very famously-repeated phrase
IT IS A TRUTH universally acknowledged that a single man in possession of a good fortune must be in want of a wife.
A good fortune. This makes us wonder to what extent "a good fortune" is a wish, or an expectation, in the society of the Bennett sisters in the novel. Then, we wonder: why is "a good fortune" the catalyst that would drive a man to consider marriage? This is what serves as evidence that economic concerns INDEED touch the lives of the characters.
The Bennet sisters are particularly affected by economic concerns because they are females. Regency England, the time when the novel takes place, is a male-centered society where only males predominantly, but not exclusively, inherit. Hence, the Bennet family consists on five sisters who will each inherit a fifth of their father's wealth except for the land, which was entailed to the male line. This particularity affects Mr. Bennet, for he admits that he had never saved enough to provide a good dowry that a potential rich husband might want. This is why Lydia ends up having to be rescued by Darcy with a dowry in order to "buy" Wickham to make him marry her after they had eloped.
Furthermore, the Bennet sisters' home was entailed to a distance cousin who would be the next male heir to Mr. Bennet's branch of the family. His name is Mr. Collins, and he is a far cousin to the Bennet sisters. He is also stuck-up, annoying, overly dramatic, and quite unattractive to anyone who would want to marry happily.
His own economic concerns are the preoccupation with pleasing a member of the upper classes who is his patroness, Lady Catherine DeBurgh. In his case, having her patronage is like going up in social rank, which allows him to be condescending to others.
Naturally, Mrs. Bennet's (the girls' mother), fixation is to marry her daughters off to men who are well-to-do. This is what would guarantee a woman her place in society, especially upper class, gentleman's daughters like the Bennets. This is also one way a woman would come into some property, especially if the husband has plenty of land and money. However, Mrs. Bennet goes one step above and is actually a bit obsessed with it. We see that obviously stated in Chapter 18 when Mrs. Bennet speaks aloud of the prospect of her daughter Jane's marriage to Mr. Bingley and of how this may bring other opportunities to the rest of the daughters. It is a most embarrassing thing for her to do, and makes Lizzie nearly lose her temper at the ball.
It was an animating subject, and Mrs. Bennet seemed incapable of fatigue while enumerating the advantages of the match. His being such a charming young man, and so rich, and living but three miles from them, were the first points of self-graduation; and then it was such a comfort to think how fond the two sisters were of Jane, and to be certain that they must desire the connection as much as she could do. It was, moreover, such a promising thing for her younger daughters, as Jane's marrying so greatly must throw them in the way of other rich men;
Hence, social status, financial security, and personal ego are some of the ways for how economic concerns touch the lives of the characters of Pride and Prejudice.