Adding products on Shopify performance parts website from manufacturer websites (most copy/paste) - repost

I need to add a lot of products on my website, but I don't have the time to do it. I want the new product descriptions, title, pictures & other content to be all on the same pattern as I already made on current products. I currently have about 3500 products, but need maybe 8 to 10.000, probably more. All the collections are already created, you just have to associate product type (or create if no products are currently associated) according to the good collection, and associate or create manufacturer brands. Some items can take 15 seconds to create (for the same item type/brand, Click Duplicate, Change title, car years, and change 1 or 2 pictures, by exemple) and some can take 2 or 3 minutes. Some of the current items have to be modified a little (add brand logo on top of description, reformat the text). I'm selling car performance parts, so a good knowledge in this matter is a must because all the information have to be 100% accurate. Wheels, oils, suspension, brake parts, engine parts, safety equipment, tires, car electronics (sensors, engine control management, not audio/video electronics), car plumbing and more. Most manufacturers don't supply products pictures, so you have to save the pictures from their website, modify them in photoshop (adjust canvas size). On some of those websites you can't use the "save as" function, so you need to take printscreen, then crop pictures. The website is on Shopify platform, easy to use and accurate. A Shopify knowledge is a plus, I'm using the new recent version. If you are not sure about a product, I can help, I want to work together with the freelancer to be sure that everything is 100% accurate. I'm using Facebook messenger a lot, and also have Skype account. You don't have to add weight or price on the items, but put the inventory to 0, so the item is visible from Google, and customers can see that the items are available, but not the price. I'll add prices and weight after the product is created. Some products have video, product specification images or PDF instruction links to add to description. I will create a list of the items or brands I want to add, ordered by importance. I do not have thousands of dollars to invest in this project all of a sudden, my company is at the stage of start and I have a lot of expenses, so the project can be spread over several weeks so I can have the time making funds for this project.