How many websites can we sell our songs on? Do we have to use just one?

I was thinking about Sound Click, Band Camp, Sellfly, and Song Cast Music. Which ones are the best?

As many as you'd like.

There is no exclusivity that I am aware of when you sign-up with those platforms. But if there is, be careful.

They generally get your songs into retailers sometimes on and off-line. It is extremely competitive though. The payout, even with a decent level of volume can be really minimal in all reality.

Read the agreements before you sign-up because there will be a "piece of the pie" taken for various things. Some may focus on ongoing fees to keep your songs or albums on the platform. Some may take percentages of revenues. Most will offer help in getting everything setup so that your sales can be tracked.

Each platform will have a slightly different business model.

Well, the reality is, people don't buy music any more. The sites you mentioned are basically sites where other songwriters and artists put their music, not many real music listeners go to those sites. And basically music is free just about everywhere, YouTube, Spotify, other streaming sites.

Playing live is the only way to make money with your music, or having somebody play your music live.

I know a guy who has won several awards for songwriting. Has won contests, has been on stage with some big names, and his main source of income is his weekly gigs at bars and eateries. And even gigs are hard to find these days

Band Camp is good but your best bet is to put them on CD Baby and let them distribute the songs to lots of other sites including iTunes, Amazon.com, Spotify, YouTube, etc. It's a business of pennies. Streams will earn you 1/100 of a cent, but occasionally you will get an album or song download. You need to promote yourself and send people to your download sites using Facebook or Twittter, etc. Make videos even if it's just a lyric video for YouTube. Play live. Don't quit your day job.

I am not a commercial guy. I have pressed records and CDs in the past and have given them away. My songs are at Cdbaby and itunes, but I am only interested in money coming from major publishers and record labels.