I do a fair amount of single parent surrogacies.  The stories behind the surrogacy range from persons who never got married, to persons who never wanted to be married, or simply to persons who put their career before a family.  

One successful physician I helped even joked, "I want children outside of marriage so I never have to address the issue of child support." 

Regardless of their individual motivation, each single parent I represent concludes that they can have a child even if alone and despite the fact that they will need the support of a gestational carrier.

We can all say that guiding a surrogacy through the medical and legal systems requires experience on the part of the agency, clinic and legal practitioners.  We must remember though, things that are taken for granted when representing couples, as for example guardianships, have to be specifically addressed when representing singles.

You might want to read this article. http://www.proudparenting.com/node/1893  I enjoy any story with a happy ending.