Its against the law to sell used carseats try craiglist free section
They do...but check how new they are. Car seat regulations change almost yearly. Sad to say...better off buying new.
They very rarely have them. Try a second hand childrens store like Once Upon a Child
My son did volunteer work here, they do receive car seats and strollers every once in a while here. Your better off buying one buying a car seat brand new.
Sometimes local police depts give away car seats to those in need.
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