Construction of track - help with costs please

["Andrew Robson" <ajrobson@gil.com.au>]

I need some help to work out the cost of constructing two sections of track.

The first would be 300 metres of curved 3'6" track, with three sets of
points, to form a wye across the throat of an existing junction.  This would
allow trains to leave a down line, cross an up line, then travel in a wye
across the throat of an existing junction (in the opposite direction) from
the up line.

Existing
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Required
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The second would be a set of points leading of an existing 3'6" line, with
about 500 metres of track, and two sets of points forming a passing loop to
facilitate locomotive escape from the branch line.

Existing
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Required
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I don't want to go to the state government railway just yet for various
reasons, and am wondering if anyone inside or outside Queensland with
experience of this or similar guages can help me out please with realistic
cost estimates for Australian construction?

The track would need to be capable of handling heavy wagons.

If you can help, please post here or email me directly on
ajrobson@gil.com.au

Andrew
Brisbane