True on both counts, although I believe the Mars Direct price-tag came from the same agency/group that priced out the 90 day report.

Design Reference Mission 3 was remarkably similar to Mars Direct, but DRM 4 and 5 have grown a bit from the minimalist approach, although they still revolve around In Situ Resource Utilization, just as Mars Direct did. DRM 5 is especially confusing, and it will be a year or two until we see DRM 6, so I actually think the 2011 edition of The Case For Mars is about the best book out there for demonstrating that it can be done. Obviously the rocket he describes was based on minimally altered space shuttle manufacturing capabilities and architecture which no longer exist, but the design principles haven't changed. Zubrin currently endorses a couple versions of Mars Direct based around SLS and/or Falcon Heavy. If you are looking for modern, the most modern Mars architecture I know of is Buzz Aldrin's current version of his Mars Cycler concept. I haven't read his new book yet, but as I understand it that's a grand architecture for a massive project, rather than a minimalist approach. I'm sure we could do it for a fraction of the cost of the Iraq war or the bank bailouts, but that's still many times larger than NASA's current budget. I haven't looked into the political viability, but I suspect that anything over a quarter of a percent of the federal budget isn't likely. I was trying to discuss how it can be done, rather than how to do it best. I'm definitely all in favor of Buzz and Elon if they can make their visions a reality.