Going it alone is not going to get you anywhere. Organise through your committee to get an inspection of the whole building, and then get the developer to fix the defects.
The OP is talking about minor or cosmetic defects in his apartment which are only covered by a two -year waranty. The strata committee is not going to take any interest in lot property defect claims – it has nothing to do with them. Likewise, apart from possibly sharing the cost of an inspection visit with another owner, the lot-only defects are between the lot owner and the developer and no one else.
The claims period for major defects is SIX years, not seven, and they should be pursued by the strata committee and the owners corporation, not individual owners.