Mastering 4 tracks

I’m looking for someone to master 4 tracks initially. Could you please let me know what format you require all the best, Holm

Additional info:
I don't have a hard deadline for this. Check out the song I attached. The song is mixed and ready to be mastered. I'm an indie artist. I'm interested in working with a very experienced mastering engineer. I'm looking to master 3-5 songs.