...is that for DD this is apparently not simply a financial investment plan, but a lifestyle plan as well. So the question is not simply, how do I save for college tuition, but how do I save for college tuition and have a second place for the weekends, etc., as he described in his original post.
The first hurdle is obviously whether one can afford a second place at all. You'd have to test the costs of such an arrangement, which could be home ownership, long-term rental, or a bunch of short-term rentals, and then decide on the solution that maximized both the financial feasibility and the lifestyle outcome that you're looking for.
I sold houses for several years before becoming an appraiser almost 30 years ago, and I quickly decided that many home buyers are motivated irrationally. I eventually modified this into a realization that of the things we either need or want in life, some of them are satisfied tangibly via money or money-equivalents, and others are satisfied less tangibly, e.g., living close to the grandparents, living in a diverse community, or spending summers by a lake.
(This latter theory has made it into eminent domain law as Richard Epstein of the Federalist Society and Harvard--formerly Chicago, where I'd met him--has discussed in his 1985 book, Takings, and then more recently in an amicus brief in the Kelo case, arguing that property owners, particularly residential homeowners, deserved to receive compensation for "subjective value," as in, "This is the house my mother grew up in and the one I grew up in." After Kelo, a number of states adopted new law that required payments in excess of 100% of market value for the real estate taken by eminent domain. I'm digressing, but the idea that there is more than money value to our personal real estate holdings is well-supported, I think.)