When your female takes a BARE minimum of 30 months to reach the minimum breeding weight (and actually 36 months is ideal and still followed by many) ....you want to buy your females first when your intention is breeding either now OR the future.... EVERY time. Breeders do not cough up mature females with good genetic potential without some serious $$$ on the table. Sure you may be able to find a mature het, but then you also aren't guaranteed that SHE will lay either.
You can have a 1 1/2 year male ready to go, but then you STILL have to find at least a 3 year female to pair him with .....ever price mature females from breeders?.....they don't like to give them away for obvious reasons het or not.
The "other guy" who said to get females first is an actual breeder.....