OK, let's assume that no investment money is ever used. Only excess salary. If one person pays cash, and another finances 100% of the initial buy in for 10 years (a very bad idea), for the first ten years the yearly cost is almost exactly the same. One pays rack rates, the other pays Maint Fees and payments on the loan.
After ten years, the first is still paying cash, the second has paid off the loan and the cost drops to less than half.
Both still have exactly the same investment portfolio. If the dvc member chooses to sell early after the loan is paid, they are WAY ahead.
No matter what, there is no cash rate or discount that will beat DVC if you pay the long game
You're still using rack rates. I don't pay rack rates. No one should.
Discounts and renting DVC points are options.