I have had a look bearing in mind I have done so on my blackberry and not the pc.
What is your contingency if the build time runs over?
what is your contingency plan if it takes longer than 3 months to sell?
Have you got cash flow to pay the loan? Is it close to 5k a month?
Have you factored gst or cg where applicable?
Have you factored site costs incl slab or sub floor if applicable? Are you 100% that is included in the construction costs? I'm sure you previously mentioned that the costruction price was based on an estimate.
Does the construction cost include gst? Does it include the builders margin?
Do your costs include driveway and the usual stuff that builders don't include such as window coverings?
Will the site need a retaining wall? If so, it's an additional cost.
Sorry I can't remember but will each unit be on a seperate title and if so has that been factored?
Have you included soil report and site contours? This should be done following demolisment.
Have you factored in additional cost such as screw piles if they are required?
Most importantly if interest rates were to rise an additional 2 points can you cope with the additional cost?
Are there fees if you discharge the construction loan within the 14 months that you expect?
Have you factored LMI for construction loan?
Insurances if applicaple?
Solicitor and accountant fees on sale?
I'm most concered that you haven't included taxes on sale. That would put a pretty dent in the profits.
You have all the major stuff estimated, now I have provided the nitty gritty as food for thought.