Even my 1947(?) Craftman (Atlas) 12 x 36 (120VAC) does not have the much needed larger headshaft hole and once the stock is held and the talistock brought up it is less than 36 between centers. I have looked at the Grizzly and Jet products and the packages c/w some tooling are attractive, not to mention the larger hole is already there. I dont do bigger stuff anymore anyway, so it is a fine machine for me, but when the odd rifle barrel project comes along I can only get a skinny one backed in. These mini and micro cannons are getting me interested again (and, as an old guy, Ive come to believe that a man's toys should best be something he can move himself).
BTW, Ive had the old Unimat SL's ,one set up as a lathe and the other as a mill (mostly toy machines), a Unimat 3 (better), 3 Atlas 6 x 18's (all pretty worn out), a Logan 9 x 24 and this Atlas 12 x 36 (now for some 30yrs). It is nice to have a smaller machine or two around to do small jobs or not break down a set-up on one for a quick job or another step. If you get a nice 'small' machine it can continue to serve you well if/when you get a bigger one.
My mill is a deluxe Sherline with the DC motor, and within its size limitations is a dandy little machine. I think the Sherline products are way better values that the Unimats (and their proprietary high priced tooling, etc.) and the DC makes for a high torque good bite cut. Made in the USA too. They are a fine 'model makers' tool and far better than the small 'Pacific Rim' machines at such places as Harbor Freight.
Since I can understand where you are coming from with the posted question, and wanting to avoid costly mistakes, your are wise to get the training and go through the learning curve before buying a piece of junk. Just off the top of my head (and not having perused a catalog in some time) I think you would be looking at about a min.$4000 in lathe/tooling/fixtures to get into a medium sized Jet or Grizzly. If you drop down into the $2000-$2500ish range you can get a pretty good package that will do (probably) 95% or better of what you want to do.