The cost of not buying could be way steeper than the few dollars in cash flow you get from waiting for the perfect place.  

For your question you posed, two factors would influence my decision: 1) my opportunity costs - in other words what other options do I have at the time, and 2) My stage of life - at points in my life I have been willing to take a bit more risk, and have had bandwidth to take on that risk, and others I am not so willing to take the risk and do not have the bandwidth. 

Deduct carrying costs.

Loan should be CTC within a week of contract and investors enjoying the property and filing their STR permit application for Summer..Rate on a 30 year fixed was in the high 6%'s...big job's report tomorrow that could accelerate rate cuts..stay tuned! 

In Gary Keller’s book, Shift, he lists 25 creative options that are most common, but barely scratch the surface:- Seller Contributions- Seller-Funded Permanent Buydown- Seller-Funded Temporary Buydown- Owner Financing- Contract For Deed- Seller Second Lease Option And Lease Purchase- Seller-Assisted Down Payment- Wraparound And Assumable Mortgage- Gift Funding- Selling And Refinancing Existing Assets- Non-Occupied Co-Borrowers- Using 401(K)- Temporary IRA Transfer- Pledged Asset Mortgage- Equity Transfer And Bridge Loan- Employer-Assisted Mortgage- Lender-Funded Buydown- Fannie Mae’s “My Community Mortgage”- Running Scenarios With Automated Underwriting Systems- Adjusting Amortization Period To Lower Payment- Adjusting Interest Rates To Cover Closing Costs- State, Province, And Local Grant Or Bond Programs- Mortgage Credit Certificate- Private LendingHe said these options barely scratch the surface.

Once you have a few under your belt and are confident on renovation costs, have your team in place, etc., you might roll those dice.

What tool can I use to track the costs of this total project to see if it makes sense ?

Generally not optimal for maximum ROI but for offsetting second home costs. 

The Motivated seller house is valued at 254,000 I offer to  am offering  to purchase the house at 75% of the appraised value which is $190, 500 and  pay closing cost of $ 7620 which is 3%.

Hi Tahreak, You have to be just as careful purchasing new builds, many of the homebuilders I noticed sometimes cut corners and you might have more maintenance related costs than expected.