Two brothers have jointly purchased 1350 sq yards of land in two phases, but their registered documents only account for 1200 sq yards, with 150 sq yards initially set aside as a common path. Now that they are the sole owners, they wish to regularise this path, potentially merge it with their plots for Vastu compliance, or explore development options. They are seeking guidance on how to officially include the path in their ownership, get building plan approval for it, and whether the original seller needs to be involved in any new registration process.