Perhaps the two you gave away were pullets. If they're crowing, they're assuredly cockerels. A hen may crow occasionally but pullets don't.
A farm without a very experienced sexer probably will send out lots of cocks unless they have a feather sexing breed.
Chicks hatch at a 50/50 ratio and even big hatcheries with high paid sexing experts can get it wrong.
I wouldn't suggest starting with fewer than 3 and even that is really not enough for many reasons.
First of all, you probably got them for eggs rather than meat - right? As you've said, it takes a lot of time and money to get started. To go through that and still have to buy eggs from the grocery store seems like an exercise in futility.
Regardless of how many eggs you currently use, you'll use many more once you have delicious fresh eggs in your own yard.
Even starting with all females as chicks, it's a 5 month wait for the first little pullet eggs. RIRs will eventually lay nearly an egg a day till their first molt. That's usually the second autumn. So if you only average eating and baking with about a dozen a week, you're ok with 2. But during the molt you won't get any eggs, so that's 2 months or more with no eggs.
After each subsequent molt they will lay fewer and fewer eggs.
Also, chickens get taken by predators, get ill or just die for no apparent reason. As flock animals, they don't do well without friends. If one dies, the other probably won't fare well unless it has made friends with other animals. To add birds later is more difficult.
