purchasing commercial property

Hi, I’m sure there must be some one out there who could answer this from an informed position but my experience tells me that whether you pay gst on a commercial property is dependent on the position of the seller. I purchased a commercial property 4 years ago and did not pay gst. The previous owner had owned the property for 20 years which meant he had purchased it prior to the days of gst and i assume had not registered for gst after its introductionn?? I’m also have not registered for gst which means I don’t add gst to the current rent. I assume I could sell it with out adding gst but I guess I need to ask my accountant that one.
I’ve been to a couple of rate recovery auctions (conduct on behalf of the local council). The properties for sale were residential but I noted gst was applicable in these case which again makes me think it is the status of the seller which determines whether gst needs to be applied.
Not too sure what you’re asking about the rent? If your asking how do you determine what you would actually charge per year, the best bet would be to talk to an agent or do some home work on like properties.

hallg