I have my library on my laptop and i just installed it on my home computer I uploaded all my books onto it all 4000+ ( no doubles i cheacked

) Is there a way to keep them both current when i download or add books or must i keep doing it separately?? Is there a way to save the books ( i have to change them to look right, correct the titles, authors and etc) so that if i have to reinstall or put calibre on another comp i wont have to start from zero?
I really need help!
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