we had an owner who didnt pay for 5 years, our condo organisers took her to court and were on verge of repossessing her apartment when she paid up! meetings held once a year not well attended but usually we have a quorum and can vote things through. we all keep in touch via e-mail and such so know whats going on = perhaps you could contact those owners who havent replied this way?

Besides the condominium rules, you may have to consider municipal by-laws and building plans. If it is a fixed structure, you may have to have municipal approval. A number of years ago, in one of the local apartment blocks, there was a court case to force the ground floor owner to remove a structure he put up without proper planning.