I'm just curious how accurate it is compared to what you all have experienced.

i am interested to see if the Bigger Pockets calculators are used in Canada and if they are as accurate, or if there is anything i can do to tweak it a bit to make it more practical for Canadian use? 

My hesitation is how easy is it to actually back out.What should be in the contract to ensure that I'm able to renegotiate the price or back out completely if the scope of work is not represented accurately?

I have put in a lot of time and effort into learning what it takes to accurately and ethically quote buyers and sellers on properties for assignments of contracts from seller to buyer (I know a lot of real estate agents feel that this walking a very thin line & many believe it's even illegal-also not sure what to make of that). 

It is not 100% accurate but that depends heavily on how clear people are speaking. 

Without any more knowledge than what’s contained in your post it’s an envious position to be in and there are a wealth of options available to you ranging from a joint venture to self performing on a new development to long term hold.The only people who will be able to accurately answer your question are a licensed appraiser or a broker(s) who specializes in land or commercial/residential properties.

Not having more info I would gamble that your price needs adjusting .  

If the numbers you posted are accurate, it looks pretty good to me. =)

The receipts will serve as ultimate proof for an audit.Your data in QuickBooks should be accurate as long as you are reconciling to a bank statement each month and categorizing appropriately.

based on the analysis it looks good, but i am not sure if it is accurate.