Hi Sarah! Congrats on the free greenhouse, free things are always the best!!!
Beefy is right, we got a free 10' by 8' greenhouse (and moved and errected it ourselves) not so long back (Octoberish time), it wasnt majorly difficult (tho getting it into / onto Mr D's Fiat Panda was fun!), but I would advise some good gloves, a couple of permanent marker pens, lots of screwdrivers, pliers and spanners and some WD40 or equivalent for dismantling, plus treat yourself to a load of new nuts / bolts / z-clips and w-clips, as using new ones will make life a lot easier! You can get them quite cheaply online, and also take a look on ebay, some places on there do them very cheaply indeed!
Oh, and give it a really good clean before you put it back together, including the glass, it is a long job, but much easier whilst dismanteled!
You can read all the advice we were given and all about our greenhouse adventures (plus see the piccies of it in all its glory) on the vine thread we started about it here
Chance for a free greenhouse!
Anyhows, hope the reply was of some use, hope it dismantles easily for you and you have a trouble free move, and of course, good luck!
