I don't know how accurate this [1] is (because the citation link is dead), but Wikipedia claims Veronica Mars cost about $1.7 million per episode ($2.1 million for the Season 1 finale). Each episode is 1 hour, so double that, and you assume that the movie would cost about $4.2 million if it had the same quality as the show. And that's not even taking into account that the director and Kristen Bell probably will do the work for less since it seems to be a pet project of theirs. Overall, it seems like it'd be really easy to make back the investment on this one.

1. https://en.wikipedia.org/wiki/Leave_It_to_Beaver_%28Veronica...