Other than the fact I know lots of other surrogates and intended parents and see pictures of the babies every day?
Yes, that is called anecdotal evidence.
I genuinely don't understand what you mean by evidence?
Academic studies, statistics produced by one of the bodies you mentioned. That sort of thing.
Why would loss of earnings etc be seen as personal gain?
I'm not saying it is, I am just trying to get a handle on how 'not-for-profit' surrogacy works.
As much as you hear little about surrogacy there have been cases where the surrogate ends up out of pocket, so for some to claim its usual for surrogates to receive 18k in expenses is ridiculous, Expenses must be reasonable and justifiable.
Again you make these claims with no evidence to back it up other than somebody told you?