Porsche 718 Boxster/Cayman GT4
The Porsche 718 Boxster/Cayman GT4 market indicates a moderately probable upward trend (0.53 to 0.6) over the next 6 to 24 months, though within a volatile regime, supported by a confidence of 0.935. This outlook notes a depreciation risk of 61.06 and appreciation momentum of 31.37. The strongest leading indicator for this market is the Case-Shiller National Home Price, with a correlation of 0.73, leading by 10 months.
What It's Actually Worth
Blended value of a standard 3 yr, 4k mi example, ~$156K now. The green line weighs confirmed auction sales most heavily (the amber dots — what cars actually hammered for), blends in fast-selling "just-missed" listings, and lightly smooths out month-to-month composition noise.
Did our model work? 61% direction calls right
Each faint amber line is a forecast we would have made at that point in the past (12-mo horizon), drawn against what actually happened (blue). Over 36 scored forecasts: 61% got the direction right, median value error ±16%.
Walk-forward: each ghost uses only data available at that date — no hindsight. Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Auction Scorecard gavel in range 9 in 10
We replayed 213 past auctions in this market — predicting each hammer price from market data before the sale (no hindsight). Typical miss: ±18%; the gavel landed inside our predicted range 9 in 10 of the time.
| Sold | Car | Our range | Hammer | |
|---|---|---|---|---|
| 2026-08-06 | 2022 · 2k mi | $112K–$248K | $130K | ✓ |
| 2026-08-04 | 2021 · 4k mi | $106K–$234K | $120K | ✓ |
| 2026-08-03 | 2023 · 4k mi | $103K–$228K | $198K | ✓ |
| 2026-07-30 | 2022 · 8k mi | $90.5K–$200K | $134K | ✓ |
| 2026-07-23 | 2022 · 9k mi | $88.4K–$196K | $181K | ✓ |
| 2026-07-21 | 2021 · 11k mi | $85.8K–$190K | $117K | ✓ |
| 2026-07-08 | 2023 · 4k mi | $102K–$226K | $159K | ✓ |
| 2026-06-25 | 2023 · 2k mi | $109K–$240K | $137K | ✓ |
Live now — calling it before the gavel
We're currently tracking 8 open auctions in this market. Here's our predicted hammer range for each — check back after they close.
| Closes | Car | Source | Our predicted range |
|---|---|---|---|
| open | 2023 · 3k mi | BaT | $97.2K–$276K ($164K) |
| open | 2019 · 16k mi | BaT | $78.7K–$224K ($133K) |
| open | 2016 · 6k mi | classic | $85.8K–$242K ($144K) |
| open | 2022 · 12k mi | classic | $76.7K–$217K ($129K) |
| open | 2022 · 9k mi | classic | $77.6K–$219K ($130K) |
| open | 2023 · 0k mi | classic | $117K–$332K ($197K) |
| open | 2022 · 8k mi | classic | $80.5K–$227K ($135K) |
| open | 2020 · 14k mi | classic | $76.7K–$216K ($129K) |
No-lookahead: predictions are made before each auction closes; the scorecard grades confirmed sold auctions only (no-sales excluded). A modeled estimate, not a guarantee. Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Where We Think It's Headed
Probability and range, not a single number. Wider = less certain (not bigger gains).
| Horizon | Direction | Probability | Confidence | Past accuracy |
|---|---|---|---|---|
| 6 mo | UP | 53% | Low | 57% |
| 12 mo | UP | 56% | Low | 61% |
| 24 mo | UP | 61% | Low | 71% |
Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.
Crystal Ball — What Leading Indicators Signal
Distinct from the trend forecast above: this blends all 8 leading indicators (each at its own lead time, de-duplicated so correlated ones don't double-count) into one signal. Leading indicators are collectively signaling lower over the next ~12 months (high conviction — 100% of weighted drivers agree), driven mainly by Russell 2000 (small cap) and Silver.
Are the indicators agreeing?
Each bar is one driver's current push; longer = more weight. All one side = high conviction; split = low.
If You’d Bought in 2021
$100K invested 2021-08 → today (5.0 yrs), this car vs where else you could've put the money. Rebased to 100 at the start; the dashed line is inflation (break-even).
What This Market Follows
Specialty-car prices don't move in a vacuum. These economic indicators have historically led this market — tap one to see it shifted forward by its lead time, overlaid on the value line.
30-Year Mortgage Rate leads by about 6 months (moves with this market, correlation 0.70). Shown shifted forward 6 months so its turns line up with the market's.
Why We Think This
Current Inventory Snapshot
Comparable Markets
| Market | Undervaluation | Appreciation | Liquidity |
|---|---|---|---|
| Porsche 718 Boxster/Cayman GT4 | 17 | 38 | 30 |
| Porsche 718 Boxster/Cayman Spyder | 29 | 38 | 31 |
Recent Signals & Alerts
- price jump Median asking moved sharply (z=-8.4)
- inventory shortage Inventory dropped (robust z=-5.8)
- inventory shortage Inventory dropped (robust z=-6.0)
- price jump Median asking moved sharply (z=42.1)
- vin returned lower VIN relisted $-31,926 vs prior
- price jump Median asking moved sharply (z=-38.4)
Data-backed market intelligence, not a guaranteed prediction. Figures are modeled estimates from asking prices, sold comps, and public economic indicators; they can be wrong. Not financial advice.