You could do some of the basics to get them going as brandables, such as creating all the social media accounts that will eventually need to be made anyway.
Two separate gmail accounts for each domain name and start creating accounts for FB, FB Fan pages, Twitter, G+ pages, Instagram, Pinterest etc, grab all the open URLs for your domains ex. facebook.com/orboy, twitter.com/orboy etc
After securing your brandable URLs in social media you can start dressing them up, maybe hire some help from freelancer.com to get those going. You don't have to buy artificial likes and follows, just make sure you have all the relevant social media accounts ready and lined up to be handed over with the domain after the sale. That will add value imo, all this will need to be done anyway for a successful brand name ... you already have the work done.