Turning screened porch into greenhouse for the winter
I started this year a bunch of succulents from seed. I can't leave them outside year round and physically do not have the room inside the house to store all of them. I would like to convert my screened porch into an overwintering/seed starting environment during the colder months. My main concern is money. I can't afford to spend thousands of dollars in doing this. My thought was to get some heavy duty clear plastic and just enclose the porch that way, but then I thought about heating it, ventilation, lighting etc...
Any ideas, points in the right direction, maybe a how-to or diy article. Or if this is just not realistic, then someone slap me and tell me to start growing things within my means.