I think the best idea would be to leave all difficulties on one page. On top of each side-job article should be a general description with the infobox (without rewards), with beneath it each difficulty getting its own heading (e.g. a green heading for easy, a yellow one for medium etc.). So they are basically split up, but still on the same page.

Check out Loan Shark. I've used tabs to basically put 3 pages into 1 - works well. We'll need an introductory page of course, to tell the player what the general Loan Shark business is.

Hey, that looks pretty good! Although I think the infobox should be present only at the intro page, because a lot of its info is the same for all three difficulties.

Agreed, but then what about location and reward? Not sure where that should go.

EDIT: also, remember that users can end up viewing the page without having the tabs - by going to Loan Shark/Easy, Loan Shark/Hard, or Loan Shark/Medium, via searching, the tab won't show up, because the Loan Shark page's tabs use pages and puts them into one. Thus, lacking an infobox on one of the subpages might not be helpful.

Though I do agree 3 infoboxes looks painful.

Still tryin' to find a satisfying solution for this matter. I've been looking if it is possible to hide certain wikia pages for the (wikia) search engine, but I guess that isn't possible - although I can't seem to reach a subpage through Google search.