Mr. Rokesmith pays a visit to Mr. Boffin, who wants to settle the terms of Mr. Rokesmith's job as his secretary. Mr. Boffin basically wants to buy Rokesmith out and out, meaning that Rokesmith will always be on the clock for whenever Boffin wants him. It sounds a lot like slavery, but Rokesmith agrees anyway.
Once Rokesmith is gone, Boffin tells himself that he's given Rokesmith too much power in the past and that it's time now to take him down a peg.
The chapter goes on to talk about how Bella often goes for walks with Mr. Boffin, and she continues to be disappointed by how mean and superficial he's becoming.
Bella spends a little bit of time with Mr. and Mrs. Lammle. But she's smart enough to know they aren't trustworthy and starts to keep a distance.
Not only is Mr. Boffin getting mean, but he's also getting more and more miserly. He even starts to admire some of history's greatest misers and cheapskates. In order to have more control, he even orders Rokesmith to move in with him so that he'll always be on hand.
When he's alone with Mrs. Boffin, Mr. Boffin gets a little nicer. But he puts his guard back up once his wife mentions how different he's become since getting his fortune. He says that life must be different now that they're rich. It's dog-eat-dog, baby.