You have to prepay the DVC and that is the main problem. Instead you could take that chunk of money and invest it in a no-load mutual fund (as just one example) and make enought money to pay for your annual WDW vacations and still have a lot of money left over.[/QUOTE=SonicLogic]
As I see it your logic is correct but it is not realistic. If your money is tied up in an investment how do you propose getting to it to pay for your vacation?

As has been pointed out, the return on your investment in a mutual fund is going to fluctuate.

This year I may see a 20% return on my money, next year I may see a 10% loss. How do I plan for that?

If I take my profit to pay for this years vacation and the market has a big loss next year, then I'm in the hole.

You would have to have not only the money in the market, but the additional cash on the side to pay for your vacation in order to leave your investment alone for the long term to pay back the 'loan' you made to yourself for your vacations.

It is just like the dependent flexiable spending account, if you don't have the cash flow for both the withdrawals to the holding account
and the money available to make the day care payments until you can get reimbursed then it can't help you.
The reality is most people don't have that kind of money laying around to invest in both mutual funds, real estate, or anything else to pay for their vacation. Vacation money is generally considered 'disposable' or 'expendable' income and the intrinsic value gained by spending it is something far different than that gained from a financial investment.
Most people will finance their DVC membership while hoping to pay it off early. In my case I purchased 300 points and my monthly payments will be around $400.00 per month (this includes maintenance fees) for a total of $4800 per year for ten years (I plan to pay my loan off in five years, eliminating a huge chunk of interest). This unfortunately means that I will have to wait a couple of more years before I buy that new truck. My family's vacationing needs generally includes two weeks a year at WDW while staying at a moderate hotel on-site; however, we have stayed at the BWI on a few occassions and although they can be expensive, we liked staying in the deluxe hotels .
With our DVC membership we now get to stay in what I would consider deluxe accommodations and for the first ten years not pay that much more than if paying cash (If I don't pay it off early). The true value is based upon the time of the year you visit, the days of the week you visit and the type of room you stay in. Let me explain how I see it.
If my family stayed in a studio at SSR, our home resort

, for one full week during the magical season (typically during the summer) and one full week during the peak season (typically during Christmas week), including weekends, it would cost 286 points, leaving me 14 points to bank for next year. The 2006 rates for those same rooms during the magical season is $299.00 X 7 = $2093.00 and for the peak season it is $349.00 X 7 = $2443.00 for a total of $4536.00. That doesn't include taxes and the other charges tagged on. If you can get a discount, which you normally can't during those times of the year, it may cover the taxes and other charges, so I'm still paying $4800 over 12 months for at least $4500 in accommodations. And if you remember I still have 14 points worth at least $15.00 each (if used during the magical season) for another $200 to be used next year. My actual plans are different from that and I anticipate an increased cost/benefit ratio for my points.
As soon as I pay off my initial investment then I will realize the true value of my membership, because now I am paying only my maintenance fees to cover the costs of those rooms. I understand that you already know this but I went through this exercise for those individuals who may be looking at these posts trying to determine if DVC is the way to go for them. There are of course other monetary factors involved including size of down payment, lack of closing costs when financing through Disney, any current incentives being offered, etc. and other non-monetary factors such as how often one travels to WDW, how important is staying on properties, and what type of accommodations you like to stay in.
This is just one way to look at. In an actual economic sense, just as you have proposed, you would have the real time value of money and inflation versus returns on investment, etc.; however, the numbers used to calculate the values achieved, although historic in nature, are purely speculative and causes me to pull my hair out just thinking about it!

Thank goodness for Disney.
Having enough cash flow to do as you have suggested is nice; however, IMHO it's not realistic for most people. According to your logic, one should not buy a car, pay for Christmas or even buy food until you first invest your money and then use the profit realized to make your purchases.
When it comes to my vacations, I won't be subscribing to your economic theory.
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