Update on the AboveMarketplace. We now supports portfolio sales. Portfolios are minimum of two domains, but can include thousands. Each domain is indexed so that each can be searched on by buyers. Compare to other marketplaces which just list a single domain, and all others are inserted into a comment box. For a portfolio with 100 domains, there would 100 hit points for buyers at AboveMarketplace, but just 1 elsewhere. If you have questions, please ask me online or privately.
Cheers!
Victor