Just to clarify, why does the (new value – (original value + cost of renovation, including legals) not apply in this situation?
I didn’t say it didn’t apply, just that it needn’t apply. This could be a bargaining chip to get your way in terms of them paying for all the legals, taking responsibility for the common property and changing the unit entitlements. The amounts might be quite small once all the expenses are taken into account but they shouldn’t be dismissed at the initial stage. Your lawyer will advise.