Adoption Options

We've found a couple different adoption agencies here that we think are worthwhile. Since we only plan to do the homestudy and post-adoption follow-up locally (our plan is to use an agency called Special Link for actually adopting a child), we're trying to decide who locally should do the homestudy. We've ensured that the homestudy will be conducted on biblical grounds (e.g. spanking is biblical not abusive, etc), so the real decision is, to which agency do we want to write a fat check?

One option is a small business ran by a Christian lady. Another is a Lutheran agency. We probably can't go wrong with either one, but we're wondering who should have the primary role for ensuring that we're a good family to adopt a child? It seems to us that this is more of a responsibility of the church, rather than just a state-certified agency. So I hope to involve our church in our homestudy. We're open to other thoughts.