I am a financial analyst and looked at my purchase from a dozen different angles before deciding it was a good idea from a financial standpoint as well as a personal one for my family.
But, since you're an accountant, maybe my viewpoint will help explain why some have seen a value in the DVC. I see you have stayed at the Beach Club the last few visits to WDW. Is it safe to assume you spent at least about $200 per night or more? That would be $180 + 11% tax.
Well, 150 points gets you about 10 nights in a studio during most of the year.
That many nights without DVC will run you $2,000 right now for a "Deluxe" on-site room, assuming you can find the $180/night rate (plus tax). And a few years from now, when the economy is doing better, etc., it will no doubt be more.
Well, you could buy 150 points for about $11,100 (my sister just took the DVC tour...for 200 points she was told she could get $2,000 off the $84/point price if she acted within 3 days and gave up her 2002 points...not sure if this offer applies to a 150 point purchase, but you would get 2002 points and could rent them for $10/point to someone). Resale seems to be a little less than $74/point, assuming all 2003 points are present.
Anyway, with DVC you pay $11,100 today, plus you'd pay $600 in main. fees this year. For your $11,100 "investment", you would save over $1,400 on a 10 day stay in a studio (a little better than the typical Beach Club room...although you would have limited housekeeping/cancel rights/etc..). When I say "save", I mean your cash outlay would be $600 instead of $2,000 because you bought the points.
The following year, while your main. fees may go up say 3% ($18/year), your hotel costs could go up even more. Assuming they increase at 3% as well, your hotel bill would be $2,060. You would save over $1,400...and even more the next year, etc.
Put together a spreadsheet showing this:
You don't buy into DVC, so you invest the $11,100 you would have spent on the DVC purchase into a "vacation account". Assume the account earns 7% AFTER-TAX (pretty good right now). In addition, every year you add to that account what your DVC main. fees would have been (e.g. $600 in 2003, $618 in 2004). But, you take out $2,000 for your 2003 trip, then $2,060 for your 2004 trip, etc. Guess what? In less than 10 years your account is out of money. You have nothing but the memories of trips.
The DVC member who paid $11,100 upfront and then paid the main. fees also had the same trips and the same out-of-pocket expenses. But still has nearly 30 years of trips to go...only paying the main. fees for the rest of the years.
Even if Disney's hotel costs never increased (and you paid $2k per year every year), your account would still run out of money after 15 years. The DVC'er would still have 20+ years to go...or could resell their investment.
Another way to look at it...
$11,100 at the start, plus the main. fees, is about equal to $1,650/year each and every year over 40 years when you use a discount rate of 7%. So for a cost of $1,650/year, you get 10 nights in a studio. Or $165/night. Pretty good right now...and no doubt incredible 15 years from now. In my example of $200/night for a room right now, increasing at 3%/year, the average cost over the next 40 years was $370.
By agreeing to spend that much on lodging each year, you will probably save 50% or more off of the room cost. And if you don't go a particular year, you can always bank points or rent your points to someone.
The last point, and it has been made many times before, is that the real reason many people join is to have the larger rooms. I just got back today from my first trip as a DVC member. My family of 4 stayed in a 1 bedroom at BCV. It was great to have over 700 square feet of space, a washer and dryer, kitchen, etc. Basically a small apartment. My sister and her family of 4 stayed in the studio attatched to the one bedroom unit (so I really had a 2-bedroom).
With 150 points, you could get 5 weeknights in a one-bedroom suite in all but 2 weeks of the year. Using $1,650 as your "average cost" per year, you'd spend about $330 per night for such a room. Many spend that much for a regular room at a Disney "deluxe" hotel, including the tax. Who knows how much that room will cost in 10 or 20 years?
And if you want to go somewhere other than Disney (as my wife and I now want to do next year after struggling with our 2 year-old for much of the trip), you can rent your points for around $1,500 (probably more later, when Disney is charging more for their rooms) and go elsewhere. A bit of a hassle, but if most of the time you want to do Disney, DVC can really lower your average cost when looked at long-term.
Maybe even when looked at short-term...I paid $70 per point less than a year ago. I could resell for more than that today and still have taken my nice trip to a one-bedroom suite.