Buy Glider without looking
I purchased my LAK 12 from a neighbouring country (Botswana) in 2003. It is the only one in Africa so I had never even seen a LAK 12 at that point (or any LAK for that matter). I paid a third of the money into a Botswana account to show my seriousness regarding the purchase (with the assurance I could get a full refund if I did not take the glider) and then met the seller at the border post (on the Botswana side). He showed me how to rig the glider in the border parking lot. I had the proof of payment for the money I had paid to show customs - and that became the import value. The importation through the border with the aircraft was challenging but managed it fairly ok. Took another 14 years, however, to finally get the aircraft officially onto the South African registry - including a period of about 7 years when the aircraft just stayed in the trailer because I could not get an Authority to Fly. I have a serious hate of petty bureaucracy since that.