assuming that the previous owner paid the architect for all their reports and documentation, any separate soils tests etc were recorded and paid for and the plans with approval were sold to you with the property then all these records should now belong to you as development approval would not have been granted without all that supporting information and if not where are they?..ask the real estate agent to ask the previous owner, the council should also have copies and i would also contact the architect as he/she might also have useful advice about your own proposal but some of the information in the old reports may now be out of date or not be relevant to a change of use from a three unit site to a renovating an existing single family home but i would expect to be given the old records if they were promoted as a selling feature and should have been included in the contract of sale and should have been handed to you on settlement and if not what extra did you pay for something that you haven't received and can be a substantial cost if you had to repeat something that is still relevant?

Thank you for your response. We thought so. I just didn’t want to assume. Settlement is not for a month or so. So I’ll get in touch with everyone and ask. We thought about going to their architect but they specialise in unit development. I’m still going to ask them though. Thank you again.

Survey and supporting documents can be obtained either from the architect, or by filling in a request of information from council. They will have this info and can give you a copy. But if you need the raw file (autocad dwg or such) you need to contact the original surveyor or architect.

if you get an approved DA, I suggest to try make use of it, keep renewing it, its hard fight to get approval for multi units.

Thank you very much for the information.