I have a 3.6m x 3.1m metal (Arrow-style) shed used for bike storage. The original timber floor – boards on softwood joists sitting on a plastic grid base – has rotted through on one side and collapsed; the rest is soft and uneven (see photos). The shed itself is in good condition and stays as it is. The job is to: 1. Strip out the old floor: rotten boards, joists and debris, and dispose of the waste. 2. Check and level the base beneath (currently plastic grid panels on soil/grass), adding membrane and whatever packing or bearers are needed. 3. Build a new, level, solid floor across the full 3.6m x 3.1m footprint – treated timber joists on a damp-proof base with 18mm treated/exterior-grade boarding (or your recommended alternative), fitted tight to the shed walls and flush with the door threshold. The space is empty apart from a few bikes which I'll move. Easy rear-garden access. Please quote for labour and materials, and say roughly how long it will take.