or get a really small contract like we are in the process of closing... a big ole 30 points at SSR!
However many points you need divided by three would still be cheaper than renting. Your costs would be pretty much fixed at the $6 to $7 dollar range for many, many years to come. Points rentals are usually $10 to $12 or so now - and I feel sure they will go up in the future a lot more than what the small dues increases would be.
If you needed 225 points each three years, your purchased points would have cost you 75 points x 6.59 anuual cost per point x 3 years = $1482.75.
Renting those 225 points will cost $2250 at $10 per or $2700 at $12 per point.
You could easily save $1000 or more each trip, and spread out the costs so that future trips aren't a big hit to the pocketbook all at once.
Of course that leads to more frequent trips, and wanting more points....