do i have recource after applying concrete stain that was sold already being expired? from a large nation wide company.my backyard is a disaster now.

Product liability requires a showing that the product was defective or did not have proper warnings on the label et al.  First, it is important to exam the paint can for specific warnings and waivers by the manufacture.  Next, assuming that there has been a showing of negligence, either because the can remained on the shelf where an unsuspecting consumer, suchas your self would use it or by not warning of such a possible hazard.  The answer to this question would require a few hours in a case law data base.  Although there are general legal principles often times the specific facts of the circumstance will determine how the laws will be applied.  Further, depending on the facts, issues of assumed risk may arise as defenses.  Most importantly is the amount of damages.  What amount would place you in a position you would have been in had the product not been defective.  Perhaps this is the amount of a new paint job.  Without knowing the size i can only conjecture that it would probably cost less then $7500.  Assuming the manufacture and the retail store are not cooperating, to enforce your rights a formal law suit will need to be filed.  However, this is an expensive endeavor and would not be feasible in your position.  However, if you choose too you could file a small claims suit which usually costs less then $100. depending on the amount of the suit.  Although lawyers are not permitted to represent in small claims you could hire a lawyer to put the case together for you and then you would present it to the judge during court.  Hope this has helped.  Remember these are just general answers and should not be relied upon but only used for general information.  If you feel strongly amount your cause you should contact me so we can discuss in finer detail your legal rights in this situation.