Hi. TBH, an impossible question to answer (as each one is subject to its own DCP, zoning, and economics). Also depends what you mean by "oversupply".
Parramatta - a huge area with zoning that almost allows unlimited supply, and the potential at Rosehill. This is offset by new and upcming infrastructure. So long term it will continue to grow.
Strathfield is an odd one. Lots of zoning issues and council issues (NIMBYISM), but north of Parramatta Road (into North Strathfield) there is the opportunity for further rezoning. Burwood, next door, is more likely to see greater growth (in terms of supply and also in demand) and is quickly becomming another Chatswood, demographically. Quality of apartments is also quite high, so I personally think Burwood is a better bet (for units) that Strathfield.
Zetland (and that whole area, including Alexandria, Botany, Mascot, etc.). Nightmare IMO. Infrastructure limited to one main rail line, and the roads are becoming increasing clogged with pass-through traffic. I know one developer sitting on several warehouses, waiting for the economics to line up before pushing ahead with development (of over 1,000 units). IMO I would not touch that area as the build quality is low, and the supply unlimited.
Liverpool has good potential as the opportunities are quite limited. But the rentals are lower, and I am now sure developers can make enough out of it just now. So I think it will be a slow burn down there.
Merrylands. Nope. Too many brick vaneer fuglies, and more prone to knock-down-rebuilds. Transport is horrible, and the economics scary (delinquency rates on mortgages also very high). Wouldn't touch it.
Castle Hill. I just don't get the Hills Disctrict to be honest. To far away from the CBD, and highly reliant on a metro line that is going to be so goddam crowded in a year or so that people will be queueing to sell.
So of all of them, the safe bet - In my uneducated opinion - is Burwood. That's why I bleat-on about Canterbury, as if you wind the clock forward to 2050 Canterbury will look exactly like Burwood (but is currently only 60% of the price).
All guesswork from me though.
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