Exclusive means that beat can be sold only once to only one artist, buyer will receive WAV or WAV Trackouts for the beat so he/she can get the best possible quality of his/her project, licenses that buyer gets are:

Exclusive License 
Premium Professional | Beat Brokerz

Depends if buyer purchase beats on Dreamer Beats or Beat Brokerz

Non-Exclusive also known as Lease means that beat can be sold unlimited times to unlimited artist, buyer will receive Untagged MP3 version of the beat, and the license that buyer gets is:

Non-Exclusive License