wheeled chairs? u mean like an office chair? not a good idea imo cuz later u might slide backward if u slam the throttle/brake pedal. 

anyway not necessarily need cockpit, start off small, slowly upgrade when u can afford/willing to spend.

I'm not using cockpit too, just a normal computer table, but still a comfortable and racy setup to race in. 

I use one of those cheap plastic chairs as my racing chair. Can't use my usual chair because it has wheels; I'll roll back every time I wanna apply the brakes