Both seller and vendor sell property, goods or products.
Vendors sell their products to endusers, so they are at the final stage of a trade or a business. Often, they are local sellers, or it can be a person selling something in the street. They are not employed either in full-time or part-time, they are rather hired. Vendors are fixed, they are well-known in the market.
Vendor is also used in information technology for a company distributing software, while manufacturer is a term used to describe hardware distributors.
In contrast, sellers sell their products not necessarily to end users, they sell products to potential buyers, as well. A seller is a traditional term used for those who sell a property not as a merchant but an individual.
They differ firstly in that a seller is typically used for a person, while vendor can be a company or a person which is engaged in the profession of selling something.
