Like most MLP unit holders, my taxes are turned in later than usual. My filings were done last week for tax year 2013. During 2013, my units with CPNO merged with KMP. My CPA - who usually provides his serves at reasonable fees - noted that there was $700 extra charge for the time spent calculating the changing basis on that transaction. That was close to 20% of the total tax prep bill. The run rate annual distribution on that small investment (it was slightly less than 1% of my total investments) was close to $800. So I lost 87.5% of that 2013 cash flow (or "distributions") from tax prep costs alone.
KMP will be merging with c-corp KMI. Heck if I know for certain that I am saving 2014 tax prep time by selling my units before the merger. But I sold anyway. Once burned - twice scared.
There is some consistency with CPAs on the effort they go through for tax prep on a given transaction -- because they, too, are using tax prep software. So I have some expectation that my 2013 "prep costs" are an event that will be replicated for many CPA using potential purchasers of KMP in 2014.
If you like KMP (or EPB), buy KMI. At least check with your CPA before you buy KMP. If you buy KMP, don't buy a tiny holding. The tax prep costs would probably be the same if it was 1% or 20% of your portfolio.