Read books, seek mentorship, and understand costs.

They will cost $100k to get going and having to have an audit done to comply with sec requirements let me tell you is a blast (insert sarcasm).

I like how you included almost all costs (I did not see holding costs during rehab).  

Would be amazing to spend less than 1/3 the cost and save days...

Are they going to just place a lien on the lot and bill me for the demolition cost or should they bill the owner for the cost as I don't own it and only have the tax lien? 

That said, deductible would likely be $500 or more so how many nights would they need to get a hotel for instance and what would it cost?

. - Costs and Returns : In overly general terms the cost of doing business in Oregon, (especially on complex property types) is more manageable in Oregon in comparison to let's say...California?

Well besides the hard costs (construction, materials) and soft costs (permitting, architecture, fees, engineering) people often forget holding costs. 

You need to factor the cost of refinance (average $7K which may change depending upon the price of your home)

I understand I have to find the right loan and do the math, but is there really any other downside to the FHA and that additional insurance cost?