@NotBadConsidering
I totally agree that the difficult questions should be discussed. The application forms of the reputable organisations are too lengthy to post here, but are easily found online. They cover expectations, family support, expenses, amount of contact, beliefs and preferences, medical info, criminal record checks, and to attend an info/advice session.
The surrogate and intended parents should take time to get to know each other well. It shouldn't feel rushed, or transactional. If it turns out they disagree on something fundamental or just don't feel it's the right relationship, they need not work together.
When they're ready to begin, the organisation arranges an agreement session for all involved, where all the "what happens if..." questions are discussed in detail.
Additionally, if a clinic is used, the clinic provides an implications counselling session for the surrogate, and separately for the intended parents.
The surrogate and intended parents have access to a supportive community online and in person, so can talk with others in similar situations or who've completed a surrogacy arrangement.
There are other groups and individual arrangements who may do things differently and no-one would deny that problems can occur at times. But there are many in the reputable groups who work hard to uphold positive and ethical surrogacy.