Many people might like to try being an evil overlord -- at least until your scheme runs afoul of James Bond or some other smarmy do-gooder, you get to have great fun and make sure pretty much everything goes your own way.
But it costs some serious coin to ensure your unbeatability. At the link the fine folks of Creatines have calculated how much "unbeatability" would cost, based on the 1994 list by Peter Anspach, "100 Things I Would Do if I Were an Evil Overlord." The list is of ways to correct common but fatal errors to which Evil Overlords seem prone.
The estimated cost is around $14 million. While you do have some new expenditures, like hiring architects to discover any hidden passageways or secret entrances to your castle fortress (No. 52, $80,000), you also have some savings, like not having to pay to imprison your noble half-brother from whom you usurped the throne (No. 3, -$810,000)
Of course, to scrape together the $14 million, you'll probably have to start your life of crime a little bit before you start your life of crime.
Everything's complicated these days.