My baby was petite so we had him in the infant car seat up until 18 months. Having agonized over similar to you I laugh now because my baby hated the car seat so we didn’t drive much, wore him in a carrier and took the metro. He never slept transitioning from car to stroller and insisted on being out of the seat asap and into our carrier where he would nod off for hours. Go with a hand me down. that way u can always figure out what ur baby likes before u spend. We had two infant seats and learned later that he was ok in his Mesa but hated his nuna. Also he fitted in mesa longer than nuna. not sure why.
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