Maybe just a misunderstanding or something ... but, you do not want to "incubate" (hatch eggs into chicks) outside, unless you have a broody mama hen ... incubators require a very stable room air temperature, and draft free is best ... now "brooding" (rearing chicks) out in the shed could be fine ... if you have a way to keep them warm ... Point of lay (POL) while sounds easy ... may bring problems too ... are you comfortable checking for mites, or lice? Have worms? Are they really "pullets" less than one year old, or 2.5 year old "spent" hens? Can you tell the difference? How were they raised? Do you mind if they are skittish around people? How will you transport 8 adult sized birds home? Chicks on the other hand eliminate most of those problems ... and you get to know them better ... if you only want eggs ... try to find a place that sells "sexed" chicks ... this means that they can tell the gender of the chicks ... some breeds are done simply by down markings, or color ... most need an expert to very carefully have a "look see" up their back side ... If you want to hatch your own, there is a good chance you will get a few males ... what is your plan for them?