If you will pardon my jumping in, is there some way that you can limit your actual material committment to this project? Is there collateral at stake that you own? Such as, is there a mortgage where you are part owner of the property and will require your signature in order for it to become a legal transaction? If so, you can always refuse to participate.

At the very least, you can regain some of your power by talking to an attorney and finding out if there is a legal way that you can protect yourself financially from over-extension financially. I know the old mutual property thing but still, mutual property requires two signatures. And if one person refuses to sign, then there is a problem with the deal going through.

You are not stupid. And you are only trying to look out for your best interests. So be proactive and do that.

Just a suggestion.