Looking for someone to mix our song

We need 1 song mixed for our band. The style is pop-rock. Mostly live instrumentation with 23 tracks. To save your and our time, and to understand if we appropriate each other, we offer 50\50 payment terms (half on job start and half on delivery), and demand money back if the first two mixing attempts does not satisfy us. We need to mix another 10 songs, so further cooperation is possible, if the first experience of cooperation will be successful.