How many points did you buy in your first contract?
150 SSR, 2004 -- but we knew, even then, that our needs would be 200 points for "BWV, 7 nights, 1BR, every January" for a work-related conference. We started with the 150, banked the first year (as we already had our 2005 reservation booked via exchange) and knew we had a couple years to 'catch up' as we burned off those banked points.
How many points do you have now?
335, all SSR
Assuming you have added more points, how long before you bought your second contract?
Our second was a 25 point cash add-on about 10-months (?) after the original purchase. Again, we knew our original purchase was below our need -- and bought the add-on when some cash became available.
How many contracts do you currently have?
Three:
- 150 points, initial purchase in 2004
- 25 point add-on sometime early 2005
- 160 point add-on in 2007
That 160 point add-on was a complete surprise. We were at
Disneyland and visited the sales center for a tour of the Grand Cal model. The 'guide' there was good -- really good. She threw out an array of incentives (a pair of APs for either DL or WDW; a matching set of Developer points; etc) and then made her strike: "Oh, I see this is the last day of your current UY. You know, if you buy today you get
triple* points ..." Oh, my -- yes the triple points combined with the AP vouchers did us in!

This put us well over our original plan and we started taking non-conference "bonus" trips!
*Triple Points: We received 160 points from the current 2006 UY
plus 160 Developer Points
plus 160 points the following day (10/1) as we entered our 2007 UY.
Did you add on at the same or different resort?
All same resort; all same UY
We thought about adding on at the Grand Californian when it was announced -- but figured, as locals, that we'd never use the 11-month booking window. We probably should have added a small contract there as the dues have remained more stable than I expected.
***edit -- what do you know now that you wish you knew when you first bought (other than prices seem to keep going up).
I wish I had a crystal ball to see the future:
- How BIG was SSR gonna end up?? Wow ... 4 phases, huh? Seems the 3rd phase pushed SSR into the "overly large; too many units/owners" category. The 4th phase was a gift -- the Treehouse Units which I love.
- California -- when? If the Grand Cal had been available in 2004, we would have bought there instead, of course!
FWIW, it took us 6 years from first look (1998) to first purchase (2004). In between we went from "no timeshares" to DVC as our 4th timeshare. No regrets on those other timeshares -- we do quite well vacationing.

As for the DVC purchase, the most important lessons learned here and employed in our purchase:
- Multiple small contracts provide greater flexibility than a single large contract. This allows one to adjust ownership over time if needed.
- UY matters! At least it does to me ... and I resent it. Our other points-based timeshare is so much easier, more flexible and more generous! It was hard to overcome this -- but I've accepted that, to me, DVC is a 2nd-rate timeshare product.
On buying DVC, we
knew we wanted BWV/DEC-UY. When multiple resale attempts fell through, we went back to the DVC sales center and handed over our credit card to be added to the waitlist for BWV/DEC-UY. How we ended up with SSR/OCT-UY is a story of deception -- but we are OK with it. We don't feel bonded to our "home resort" -- but then again, we didn't bother visiting SSR until the Treehouses were added many years into our ownership. We had no trouble using our DVC points as intended: booking BWV each January until our conference ended in 2015. We consider our DVC points to be 'network' points and use them for visits to: Vero, Animal Kingdom Villas (multiple trips including Club level), OKW, Wilderness Lodge, Grand Cal (many, many trips -- including two this year), Aulani, etc. We were thrilled to complete a 'bucket list' trip to The Manhattan Club for Thanksgiving a couple years back when that property was offered via DVC's Concierge Collection. Going forward, I think most of our points will be used between Grand Cal and Aulani.
And how often do you have to rent out unused points?
In 12 years of ownership I've "rented out" 1 reservation to family for a solo-trip (w/out us). Other than that, we've been blessed to invite family to join us every few years in larger units w/out any expectation of payment.