Deciding to rent out someone else's uterus for your own wants and needs is wrong on every level but you also have to question the surrogate mothers status and just how genuine they really are.
Imo, there are only two reasons a woman would do this, the first is money and the other is a deep seated mental health issue. I really do not believe many are doing it for altruistic reasons.
It took me 7 years to conceive and never once during that time did I even contemplate asking another woman to grow and birth a child for me and DH. No adult 'needs' a baby. Having children is not a given right.