Putting up colorbond fence
I have actually put up a colourbond fence that way. Works with the colourbond as the posts are 2 piece, half for each panel. When panels are in place, just screw them together. Much easier to fully assemble and screw together while on the ground than when standing. You could even assemble all the panels in a shed on a windy/ rainy day and erect when the weather is better.
Re wind - pick a still day. Once they are in the ground and braced, the wind won't affect them a great deal.
Still reckon if cost is an issue go for chain wire fencing. Could use metal posts or treated pine.
Don
Easy way to install fence
The best way to put up a Colorbond fence. Set up your sting line Dig the 1st hole and set the 1st post inground then use the rail as a guide for the next hole set the 2nd post inground and build the 1st panel.You dont need screw it together yet the pannels will just clip together then just work your way along the fence line putting in each panel as you go. work form the front of the block backwards so if you have a small pannel it will be the last one on the fence. Once you have all your posts set in the ground and panels in place just level the 1st panel and screw it in place and continue along the fence.