The washing line systems sounds great Ncarver thanks so much for all the info! So much to take in :-) We don't have enough bugs invading our houses to justify putting screens over our doors and windows in the UK.
I'll start off with getting him used to the harness indoors, then when he's used to that i'll have him in the garden attached to a rope. If he likes it outside i'll think about setting up something more sophisticated like you've done!
The harness training certainly sounds interesting i'll have to get my partner to help me with that one! Will be worth it in the end though i'm sure.