Or, for the cost of a few
sheets of ply, and some
epoxy and glass, you could find an even cheaper TT720 (the original ply-built, epoxy/glass coated Farrier) and extedn it by a cuppla feet.
Paul in Nhulunbuy has one so modified, and while the curved roof on his is not as attractive, the
interior volume is vastly improved.
Another guy has cut down and widened the side berths to give more
headroom and width. Several have dded a sugar scoop.
Several guys have remodelled the forrard beam bulkhead to make a proper pass through to the forepeak, to access an area for the composting
toilet or V-berth. There are online pics showing how this is done. Actually a relatively simple modification which also includes shortening the (too long anyway) main folding beams to enable a full height walk thru.
And anyone with a tape measure and a handsaw can modify a TT720.
Although, a
battery powered circular saw, drill, driver and sander will also come in handy....
Proper little
DIY boat the TT720.
Google it.