My husband and I were sort of in the same position. I knew I absolutely could NOT go through another pregnancy. We considered adoption, but could never come up with enough money. We found adoption costs to be between 15,000-50,000. International being the most expensive. We also experience 2 friends adopting. Once from China, and one from Russia. (I think. I don't remember now, it could have been Romania. I can't believe I don't remember!!!) Both of those children had traumatic lives, and the families dealt with serious behavior, learning, and mental issues. We just didn't feel like would could handle that. I know not every child adopted will have those issues!! So many children are adopted and have wonderful lives, and never have those problems. There was just no way of knowing, and seeing our friend's situations scared us. We prayed and prayed, but we came to the conclusion of loving having an only child.
That is just my story. Whatever you decide, it's important you BOTH want it. My husband and I ended up not being on the same page with adoption, so we dropped that option. If you are on the same page, then it will work out...no matter what way you choose!! If you choose adoption make sure you are VERY through in your research of whatever agency you use. Make sure you can financially handle it, and make sure you are emotionally prepared. Talk with other folks who have adopted and get their advice. If you have all those things sorted out, you set yourself up for success!!