Want To Start Raising Frogs

The wife has a fish farm, and now wants to also raise frogs. We have plenty of tanks, but we went to look at some baby frogs and they are asking 1.65 Baht apiece, which we find pricy. Wondering, if by just going to the market and bying a few kilo of frogs, would they be old enough to breed. The rains are comming soon and I believe that is their breeding time. We could even put a sprinkler in there and maybe get them started.