Alright, so I've updated the spreadsheet. I think it's correct, anyone feel free to correct me if you see a problem.
https://docs.google.com/spreadsheets/d/1FdinzJG3G5002eJT71wkBObCj31F0jmCJmM_szQzj3Q/edit?usp=sharing
Updated numbers for SSR:
Total cost of SSR = $132,110
Total cost of Hotels = $249,471 (of note, I did not include any taxes. The $170 per night is "out the door" price so to speak)
Value of investing = $74,206 in favor of DVC surprisingly.
Cost savings of SSR over Hotels over life of contract (not including investment) = $117,361 (SSR better)
Cost savings of SSR over Hotels (including investments) = $191,567 (SSR better)
However, since you're already sold on SSR, why not try to entice you with something else? I've added Grand Floridian and Bay Lake Towers on there too. Same assumptions as the SSR, however VGF is $155 per point, BLT is $120 per point. Annual Dues and length of contract changed as appropriate for each individual resort. VGF and BLT studios also cost more points, so require larger contracts.
VGF (250 points):
Total cost of VGF = $189,229.77
Total cost of Hotels = $249,470.64 (of note, I did not include any taxes. The $170 per night is "out the door" price so to speak)
Value of investing = $122,655.14 in favor of Hotels
Cost savings of VGF over Hotels over life of contract (not including investment) = $60,241 (VGF better)
Cost savings of VGF over Hotels (including investments) = -62,414 (hotels better)
BLT (220 points):
Total cost of BLT = $148,768.44
Total cost of Hotels = $249,470.64 (of note, I did not include any taxes. The $170 per night is "out the door" price so to speak)
Value of investing = $2,640.36 in favor of DVC
Cost savings of BLT over Hotels over life of contract (not including investment) = $100,702 (BLT better)
Cost savings of VGF over Hotels (including investments) = $103,342 (BLT better)
VGF can't compete with $170 hotel rooms unfortunately, though of course VGF and POR are not quite the same class of resort. If you ignore the whole investment aspect, however, VGF is still a bit ahead.
BLT still comes out favorably, though BLT studios are supposedly quite small (I've never been in one).
Feel free to let me know if you have any questions, or if you have any corrections.