First of all you have to put them under 18 hours of light 6 hours without so 18/6, when it gets about 30 cencimeters tall and have atleast about 3-4 nodes switch to 12/12.. The whole Progress can take up to like 4 months but I'd say 2-3 months if you have the right equipment.
You can buy some dry ice and put it in a can with hot water and leave it over the plants.. this will feed them with enough Co2 for like a month.. Cheapest way.
Put the new soil in a pot dig a hole in it for the roots to fit in, take the plant by its stem and slowly pull it up, don't be afraid that you'd snap all the roots, it's a painfull thing to do if you haven't done it beofore because you get paranoid.