I have tried all types of systems from A frames to gin poles with hinged plates.
this ladder stetup has them all beat including the $200 an hour boat yard.

stand it yourself with a ladder

The mast is 35 feet, the ladder with a 4x4 post extension reaches 24 feet above the deck All you need is to suspend/balance mast just a little past the center point and have your helper hold and guide base and furler if you have one.

use the car to anchor all guy lines

tie off the legs in all directions and lean ladder against boat until you have all the guys in place. I positioned my make shift crane so it was just a little forward of step I used my spinnaker and genoa sheets for guys and a 4 to 1 block and tackle

anchor the ladder securely

you will need to experiment a little to find out how much stretch to compenstate for, we just hung from the block and tackle and adjusted the guys to stay centered over step. I did tie to boat as a safety and to keep ladder in column.

hanging from tackle to find boats center

I led the 4 part tackle to a turning block attached to mast step then to a clutch and halyard winch. This gives you precision finger tip control up and down.

up she goes as easy as grinding a halyard

once the fore and aft shrouds are connected simply run up ladder and bring down the gear.
This entire operation took only two hours and used equipment we already had.
If you did this in the water from your slip you could use a shorter set up. My boats deck is 8 feet off the ground when on the trailer.
I left out most of the details, if you really need more information to do this job you may not want to do this yourself, the rest of you should know that this was a walk in the park except walking the very top heavy ladder up while my nervous son stood on the legs.

Run up ladder to unhook lifting line