Am I On the Right Track? -- Ideas for Small, "Farm Egg" Project

I work at a produce stand which sits on about 3 acres of grass entirely surrounded by barbed-wire-topped, chain-link fence -- dog-proof when locked up at night.

My co-worker and I were thinking about proposing to our boss that, in addition to tending the stand, we could tend a small egg operation on the back of the property, which would make good use of unused space and absorb the large amounts of fruit and vegetable waste that a farm stand inevitably produces. I was crunching some numbers and wanted to know if I'm on the right track. So here goes,

Sex-linked, brown egg layers ordered in early January would begin producing eggs about May, right?

50 sex-linked, brown egg layers would produce about 4 dozen eggs/day once laying is well established and keep it good production at least until winter, right?

Assuming that they will begin going out in their runs as soon as they are feathered, they would need about 50 square feet of brooder space with at least 2-3 brooder lamps for the first few weeks and then could be kept in the 12'x16' coop until they can go out, right?

They would need about 15' x 30' for each run. But I don't know how many runs there should be to allow some grass recovery. I'm thinking 3 -- for a space about 45" x 30".

They would need about 10-12 nestboxes and 50 feet of perching space, right?

Does anyone know if any of the sex-link breeds are superior at foraging and/or more heat-tolerant than others? I'm in central North Carolina and our usual weather is HOT and HUMID.

Right now this is an entirely theoretical exercise. But after the season is over, if the info all works out, we'll propose it to the boss for next year.