250 iron nails (1-16 con needed)
100 wooden planks(1-16 con needed)
217198 oak planks (this may look like a lot, but you will get to 99 quickly) (31-99 con needed)
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Room’s Needed
Parlour.(1-16 con requirement)
Workshop.(16-33 con requirement)
Kitchen. (33-74+ requirement)
Dungeon Room..(74-99 recommended)
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This is not the fastest way to 99.. if you are crazy rich :p you can try.. from level 52 con to 99, you need the workshop room and Build mahogany tables at your steel framed workbench. You will use 92,140 mahogany planks.

This is NOT by any means the cheapest way to get 99 construction, however, it is the fastest.