Import products, categories, manufacturers from an existing prestashop to another

Hello, === THIS IS AN URGENT TASK, IF YOU DON'T KNOW WHAT YOU'RE DOING DON'T APPLY === I need a prestashop specialiste who knows what he's doing to handle a data importation task, from an existing prestashop to a new developed one, and handle any issues that may come after the import ( the developer who started the project couldn't handle the imports, he left me stuck with an uncompleted project ). PS, If you were quick and good you'll be awarded with an html to prestashop project on hold, and more ongoing work for the skilled candidate. Best, Said.