On the other hand, I do have a note in my formal bid that says project time and cost may change with unforeseen site conditions.

Since then, I have had a few clients and submitted some offers too but the deals fell through due to unforeseen circumstances (Lack of funds, seller backing out, etc).

I'm only doing this because I'm having a difficult time pulling renovations cost together due to unforeseen circumstances but I'm trying to give the seller an offer today because she's highly motivated. my back up plan is to really get to the expected bottom line price the seller wants. 

When things unforeseen occur, death or incapacitation of a family member, loss of job, being transferred in your job, divorce or such, you can sell and avoid the occupancy issue.If someone knocks on your door to buy it for 10K more for a rental, no, that's pretty much flipping it.

What you are looking to avoid is leaving it up to contractors to low ball and then hit you with all the "unforeseen" problems when you have little choice but to absorb more costs and blow up your budget.

It's certainly more risky and you should expect higher maintenance and unforeseen issues popping up during the rehab.

They would be able to provide insight to cover hiccups and the unforeseen, having navigated through it before without missing a beat!

Instead of using the downpayment we had saved, we used it as our oh-**** fund in case we ran into unforeseen problems.

I posted this question to hopefully be made aware of any unforeseen pitfalls that I am not aware of.

You will encounter a lot of unforeseen problems but if you can afford it now it will save you time and money in the long run.