Try to plan with this in mind if you can afford to do so. You will probably be glad that you did. Location and structure of your studio may also dictate the size and manner of casting that you do. Wood floors and molten metal spills make for burnt down homes. OTOH, investment casting in flasks up to, say,6 inches in diameter are very doable, given proper ventilation, etc.
Investment casting is nice in that everything's comparatively small and self contained.
Of course this is not so when you go to the more modern ceramic shell variety of investment casting, where the work can become quite large. For sand casting, building construction becomes more of a factor. You really don't want to be casting on a wood floor, even if you're working in a barn in Siberia. I've done a good bit of sand casting in my college days and no matter how well the spill containment was made, molten metal still managed to make it onto the floor on a couple of occasions. Not that big a deal on concrete, but still something to treat with the utmost respect.