The process of negotiation is nearly complete and they are about ready to sign a contract to buy the store. My parents are now requesting that I cosign for the store ownership and will not allow me to choose to back out, think it through, or discuss the situation. My sister cannot sign by herself due to financial losses caused by a recent divorce where she lost an investment in a dry cleaning store which was underwritten by my parents.
This proposal has quite a few flaws, especially on the business side.
However, I will confine my reply to the spiritual issues, for now. You certainly should consider bringing it up for discussion with our assembly when you have a chance.
Do not sign. You are not being filial to your parents if you follow a path that will cause harm to them and a lot of other living beings – including your sister and her family.
Make it clear to your family that you want to be filial but will not become involved with the liquor business in any way, even if it is only stocking the shelves or operating the cash register for free.
You do not want to bring that karma back to your own wife and family. Your parents and siblings can surely understand your obligations to your own family.
Be blunt about it: admit to them that so far you have not fulfilled your financial obligations to your own family and you are being asked to engage in something that conflicts with your family’s beliefs.
There are better ways to make a living without inflicting harm on others. In Buddhism, selling alcohol is a grave offense because it renders others stupid and creates causes for their own downfall. Also, it is not consistent with your attempt to obtain wisdom and facilitate your own liberation.
You do not have to compromise on this because it is a stupid undertaking without any doubt. You are better off incurring their anger now for refusing than to have them justifiably blame you for their downfall in the future.
As far as I am concerned, there is no filial responsibility to help inflict harm on others. Remember that you sometimes have to give tough love to your own son? This is an opportunity to do the same for your own parents and siblings because they don’t know any better!