In conclusion I am very happy with the building and budget.
Below are the total costs so far for the Earthship at this stage for those who are thinking of building their own this information would be very helpful.
Dirt for tyres and backfill 200 tonnes: $2000
Finings (for making cob) 36 tonnes: $1500
Gravel (for drainage) 12 tonnes: $500
Rain water tank(13500L) fittings/pipe : $3000
Insulation (75mm &20mm)for roof, floor and thermal wrap : $5000
Builders plastic (drainage and vapour barrier) : $400
Straw for making cob : $30
Cooling tubes (150mm stainless steel) : $900
Timber (framing and roof decking) : $2400
Re-purposed doors and windows (internal greenhouse wall) : $200
Misc building materials (screws/nails etc) : $1000
Re-purposed doors and windows :$190
Labour : FREE
In the last year I have also added to the list:
Roof sheeting and flashing, (the sheets were slightly damaged so pretty cheap) : $2600
Solar system (24 volt system with 6 thin film panels, nickel iron batteries) : $7000
Council permits, fines, plans, specialists and other vacuous expenses: $12000
double glazing for outside windows along the north face: $4200
Wood burning stove/hot water system: $1300
Affordable housing folks!!