I have to factor this in so my bid is low - but everyone else has to do that also.  

Basically the biggest reason someone might use a shipping container as an ADU is for the "cool factor."  

I know it can be a risky investment with the inability to acquire title insurance and all... what other risk factors have any of you come across?

Do not dismiss the "encouragement factor" that you will derive, simply by being around people who are already doing the exact same thing, that you are trying to do.  

However if you do want to factor in appreciation and rent bump ups it becomes a different question.

Obviously in Houston most would prefer a large home for that price, but there are still plenty that prefer condo lifestyle with no home headaches but there's one for sale right now over $5M in my building a little bigger3) David -  Like I mentioned mine is many floors higher as a comp that sold a few months back that was basically stock from the developer, mine is upgraded significantly and higher, but of course that's irrelevant now as that one sold at the time and ours has not.There's really no rhyme or reason in this end of the market, I don't expect a quick sale from my realtor but it has been nearly a year, at some point you just begin to blame the person in charge of selling it for not marketing it properly,etc.

I see real estate is a viable way for me to live the lifestyle I want and provide for my family.

What factors do you look at that show you the prices are bound to stay stable?

Terms and conditions, such as interest rates, points, application fees, promissory notes, inspections, LTV, length of project, appraisals, etc can all factor in to what makes or breaks a funding arrangement.

As said above all of these factor in.