It might take some time to finish the assembly, but I'm sure you'll be more than happy with the results. Like the guy you bought the machinery from my shop is also in the basement. I tried having it in 1 bay of a 3 car garage for 2 years, but that didn't work out. Even though the garage is heated working in the winter months was difficult. Every time I wanted to work I had to turn on the heat and wait a couple hours before anything was warm enough to touch. Even then it was a chilling experience. To top it off every time I opened a door it took another hour to get things back up to temp. Spring was also hard on the machines. On warm days the still cold concrete and iron would sweat like mad. At times it was so bad it looked like it had rained inside.
I gave up on the garage shop and moved all the tools to the basement. Like you I disassembled everyone into components I could handle, and walked them through the house and down the stairs on a refrigerator dolly. In our case the stairway to the basement is in the middle of the house. We have no walkout at ground level, or any windows for that matter. When we built the house I was traveling extensively for work. Some years it was well over 200 days. My wife didn't want any outside access to the basement to avoid potential problems.
I all there were about 2 dozen large pieces of equipment including a vertical mill, a horizontal mill, 2 lathes, a shaper, a surface grinder, a power hacksaw, a vertical bandsaw, a horizontal bandsaw, a floor standing drill press, a bench mounted drill press, a belt/disk sander, a 24"x 36" cast iron surface plate, along with various wood working saws, planers, and jointers.
I disassembled and moved all the equipment by myself with the exception of the column for the Bridgeport mill, and the motor and drive cabinet for the Sheldon lathe. Those 2 pieces each weighed in at a little over 1,000 lbs. each. There were no local rental outfits that carried equipment to move them down the stairs, and it would have cost more to buy it than to pay the local moving companies to move it.