For those doing research, check the website Australian Digital Theses Program. In Australia there is a national database of all theses (dissertations) from all the universities and colleges. The dissertations are in PDF and access is free. While I was searching the site, I turned up a dissertation by Brian Beggs from the Australian Catholic University entitled “The Role of the House Motif in the Gospel of Mark” (2005). Ironically, my own dissertation completed in 1987 is entitled “The Role of House and Household Language in the Markan Social World.” This later dissertation takes a different approach than mine; however, the type of Internet searches now available should allow for less duplication and better use of previous dissertations.
One would hope that some groups (and perhaps they have and I am unaware) would develop a database for dissertations in American universities, colleges, and seminaries.