Several things a good used machine from a private seller can be a plus in a couple ways one the lower price and the tooling you can get in the deal. I have 2 lathes Im setting up currently A 14 x 40 nardinni and a 12 X40 clausing. I bought out a friends shop when he retired. These machines were purchased new by him and spent their life in a 1 man shop. My bridge port is a 9X48 series 1 from same shop. rebuilt just before he bought it. The delta Rockwell surface grinder is a 1944 model. Along with the four machines I made 4 trips for tooling for them. chucks 3 and 4 jaw, collets round square hex standard and metric. mill vises, r-8 collets, insert cutters, some endmill ( mostly bigger ones), a dividing head and tailstock. And other tooling. steady rests and follower rests for both lathes. Draw bars. The nardinni has coolant also. The grinder had several hubs and 12-16 wheels for it. Magnetic chuck, dresser and a few other odds and ends. On top of this the family threw in almost all the stock on the racks gull lengths and cut ends from 1/2"- 3" in 10l and 4140 prehard a little aluminum and some starret gage stock. Close to 3000lbs of stock. Also got the phase converters for the mill and lathe.
A used machine may cost a little more but the extras in tooling and such out weight that.
If this deal hadn't came along for a lathe I would have looked at a grizzly or jet 12 X 40 new. Used a hardringe 10 X 24 ( here barrels can be done easily since the spindle bore is 1 1/2") or one of the many atlas clausing monarch or others out there. As to mill Index South bend Bridgeport acer jet all have some nice machines.
For safety's sake unless you have the needed equipment and skill Hire a crew of riggers or millwrights to load and move your equipment. For an idea the nardinni lathe I bought is 3500lbs dry the clausing lathe is 2500lbs the Bridgeport mill is 2500 with out readouts, vises collet racks. The crew I hired showed up on the given day at 9:00 at my friends, loaded all the equipment most of the tooling and stock. Brought to my garage set it very close to where I wanted it. By 1:20 they were picking up their toys. All for $800.00 and 3 pizzas LOL. This saved a lot of struggling cussinng smashed toes or gingers or worse. And best of all no damage to the machines or tooling.
Moving equipment with pinch bars come alongs and rollers can be done and works. Disassembling machines to get into pieces that can be handled to move and carried works. Its a lot of work and time added.