1) that's one very tall building. But it looks so beautiful you make my fingers itch.
2) I'd do the roof in cardboard. Cereal box stuff. There's also commercial rooftile stamped cardboard, but I'd sugest you make your own. The vertical tower part I'd make from plaster cast brick segments. I carved one set from a slab of dried plaster and make casts from them. I'd make the bottom part from plaster too, even the wooden planks. The support beams could be balsa. All details could be made from plaster, balsa or styrene.
3) Gosh, this is really a lovely building to scrachbuild. Sigh...
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Would anyone be interested in joining in a campaign (after the summer holidays!) to scrachbuild the top picture tower ? It would be fun to do that with a couple of guys/gals together and report on progress/problem solving.
HELLO ? Anybody out there reading this ??? :-)