Can anybody advice me on this?

Q: In our apartments 15 houses are there, 14 are occupied, 15th house in II floor is kept with the builder for the past 12 years. Being a builder he is keeping some items like windows, pipes, frames taps etc, once in a month or qtrly his persons come take the things and go. He is using it as godown, neither he is paying maintenance nor sharing expenses for the common props maintenance or purchase like Motor, Weathering, Tank repair, flooring, common drainage pipe change, common manholes, all of us would hv spent almost 25K to 30K, this guy runs construction business with his law certificate, talking too much not paying any money, we hve formed association also, how to make him understand that atleast pay 20,000 for corpus fund so that expenses are shared and our burden is reduced