If I Join DPW, do I have to only use DPW Auctions?

Absolutely not! If you sign up as a DPW member, you can use your DPW Gallery/Store, Art Tracking, and Statistics pages and sell through any combination of DPW Auctions, Etsy, PayPal directly, and eBay.

In fact, DPW integrates with eBay, just as it does with your blog, and will pull in your latests auction statuses and bids.