Following on from some advice about getting all characters to buy shares in a specific company before completing an assassination mission, how do I actually quit a mission? There's only two ways I can see how:
Save just before starting a mission, and then load once it's started. The downside here is I need to remember to save before every mission in case one turns out to be important for the stock market.
Somehow fail the mission, preferably without committing suicide, where I'm then given the option to Exit.