Ready made question bank for original Maths and verbal questions for GMAT/GRE/LSAT/CAT

For competitive exams like CAT ,GMAT , GRE LSAT etc etc i want to purchase maths and verbal question banks which can be used without copyright issues .The winning bidder must not have to make questions but rather have such developed questions which can be used by me commercially without copyright infringement ! All questions must have detailed explanation. This questions will be used for commercial purpose .So it is better that only those bidders who have serious idea of the subject bid . In fact , as qualifying requirement ,i will only consider bids of those who can show me similar work done by them before .Also , bidder must be aware that once i get the questions developed ,i shall be free to use them in whatever way i want ! So, if you have developed multiple choice questions for exams like gmat/gre/lsat/cat/sat etc and have ready made questions , maybe i can directly purchase these ...this will help save both of us time and faster project completion can be achieved ! I encourage multiple people to bid ...at later stage the bidder is expected to customise his questions and answers in a excel spreadhseet with each question having detailed explanation for each answer choice