• Making a gate on the boundary wall

Hello Sir/Madam. This is N.Bhattacharyya from Kolkata.
We live in a three storeyed Apartment where there are nine flats with different flat holders of them. We want to make a gate in a small portion of our building's boundary wall The Gate will be used for the purpose of taking bikes (motor cycle) to the posterior portion of our common space.

Suppose,eight out of nine of the flat holders are agreeing to this concept of making the gate on the boundary wall.One flat holder,who has one flat in the ground floor, is opposing this idea.This flat holder is saying that if bikes are parked behind his window (the common space for parking bikes will be behind his window ),people will come and go for parking and taking away the bikes, so his privacy will be harmed.

My questions to you are :

1. The boundary wall is common property of nine parties.If one party raise objection to the action of breaking a portion of the wall for installing a gate there,can he get the assistance of law or is his objection supported by any law? As this wall is his wall/property also (like all parties),can he say that destroying this property without his consent is illegal? Please Name the law applicable here.

2. Can any one or two flat holders raise an objection of using the common space for the purpose of parking bikes,where majority of the flat holders are not raising any objection? Please Name the law applicable here.

3. Can a minority of flat holders raise an objection for installing a shade over the parking area(to protect from rain) and an iron barrier for protecting parked bikes in the common space?  Please Name the law applicable here.

Thanks.