I spoke with the owner of the World's Best Boat Cover ... $145/ft plus shipping (to me he said ~250) ... so figure around $3500 ... and he's backed up 90 days
The rail system and CAD system they use to custom cut the covers are sweet. There's an Air Nautique they have posted (2nd row, last pic, it has an orange bottom).
However, I think I can make one, maybe not as slick but I found the material on eBay for $6.50 a yard, around 40 yards would be needed. Fabricate the track, locate pulley bearings and find someone to sew the cover ... I bet it can be done for 1/3 the cost.
The pulley system is slick, but I can't think I'd like to look at it dangling while my boat is uncovered. If it can be slipped over to cover it then a bungee used to cinch it up with a few bow type pipes to keep the front and rear taunt I'd think that's all that is needed. Make a bad to store the cover and I'd be happy!
Stay tuned!