Add multiple posts with custom fields at once.

Hi,
I’m now building a website about a specific product using WordPress, every product has his own title, specifications, and thumbnail. I am using a plugin called “custom field template” to help me customize the specifications of every product. The total amount of products is about 200, but each product comes in several modeles, which means i’ll need to post about 1000 posts or more to cover all the products with their modeles. My question is, is there any method I could use to make this process faster? In every post i need to insert a title, the post itself, a thumbnail, and the custom fields. Manually this process will take countless hours of work a day and maybe i’ll get it done after 20 days assuming i will be posting 50 posts daily which is already very hard. I’m not sure that what i’m asking for really exists, maybe a tool to help me write several posts side by side or something i don’t know. Any ideas will be much appreciated.
Thank you!