I would look to develop a unit rate from either first principles using your own contractors schedule or rates and/or internal rates for labour, materials, equipment etc. Failing that I would then look to using the Rawlinsons. Whatever method you end up using I would include your asset custodians and ensure that they are also in agreement with the rates that you have derived.
However my main reason for responding is a bit more of a side note leading from your question……..
I am curious to know for your renewal capital projects (when the assets replaced are like for like) whether the costs of demolishing and removing the original asset are being capitalised (included in the cost of the new asset(s))?
If those costs are included in the cost of the new asset then it seems a bit ironic to then revalue the assets using Greenfields assumptions without demolition and disposal costs included. If they are not being included then I would have thought they should not be capitalised from the outset?
I would be interested to hear from other councils if they are including demolition and disposal cost in the new asset(s) cost and then not including those costs when revaluing using Greenfields Assumption?
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