greenhouse newbie in Florida

[jen]

Hi everyone, It seems that my disease progressed from an interest to a full blown addiction over the summer and now I've collected so many plants that it would be impossible to bring them all inside. I've decided that I'm going to have to put up a green house and I have alot of questions. I want to decide on the structure itself and ventilation issues first, then I'll think about heating. First, I need to know just how substantial it needs to be. I live in Florida and the coldest it has gotten since I have lived here is low thirties,and even then that is only one or two nights. Normal winter temps are 60-70 day and 40-50 at night with an occasional drop to low 30's. It does not get that cold until Jan and Feb. I would like the GH to be somewhat portable or at least easy to assemble and disassemble as I don't plan on staying in my present home longer than a year or two. I have seen some that are almost like a tent the way they go up...would that be ok for my needs? Do I have to have vents that pop up on the roof or would lots of screened side windows be ok? or do I neeed those kind of vents with the fan in them....I have seen the kind of GH (tent-like) I am thinking of with one or the other of these but not both. I am thinking that the "tent-like" GH's with the fabric/plastic covers would be easier to move than the polycarbonate panels. I have also seen a Solexx model that looked easy. I am concerned about ventilation because it does get quite warm some days, even in winter and I'm not sure if it would be feasible for me to be zippering windows open and shut every morning and night. I primarily am concerned about my Phals and Vandas. I grow Cattleyas and Dendrobiums also but I think they are a little more tolerant, but I do want to move everybody to one location for the winter...except for who-ever is blooming get's to come in the house. Any Florida greenhouse growers....I need all the input I can get!
Thanks, Jen