I'd say you've got plenty of time. We recently went to Melbourne for a long weekend, bought about half a house' worth of furniture at IKEA and got it shipped back to NZ. Had nothing planned in advance, just rang a couple of freight companies from the store and had it delivered to their yard. Much of it was itemized but there were a couple of boxes of 'personal effects'. It was all packed into a container about 36 hours after starting the process, all the paperwork was done online and we paid via transferwise. I can recommend Conroy for shipping.
Obviously we knew the value of it all as we'd just bought it, but there was no need for proof of living overseas. I guess we must have given them our address at some point, but the shipping address was just to their depot in our town, and we sorted it out locally when we got back.