Okay, being in Queensland makes it easier for me to answer as that's where I practice. Check the paperwork you got from the lawyers when they did the conveyance for you. It should tell you whether there is an easement encumbering the property. Alternatively, check with them. Their usual searches will have shown it up.
It's hard to be sure from just a description, but Council will generally require an easement as part of any development/building approval if a lot does not have access to a roadway.
It also sounds like you've bought a lot with building covenants attached, which may or may not be enforceable by the original property developer. Be aware these won't generally touch the subject of easements, and are more aimed at issues like building materials, designs, height and colours.
It's hard to be sure from just a description, but Council will generally require an easement as part of any development/building approval if a lot does not have access to a roadway.
It also sounds like you've bought a lot with building covenants attached, which may or may not be enforceable by the original property developer. Be aware these won't generally touch the subject of easements, and are more aimed at issues like building materials, designs, height and colours.