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Harper Hobbies
PSA ARBITRAGE RESEARCH
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Harper Hobbies
PSA Arbitrage Research
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Year · Player · Set · Card number
Target PSA Grades
5
6
7
8
9
10
PSA Submission Tier
Minimum ROI Target
2×
3×
4×
5×
Shipping Cost (all-in)
Buy + ship to PSA + return
$
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Category ROI Target
2×
3×
4×
5×
Minimum return used when filtering category results.
Default PSA Tier
Shipping Cost
All-in shipping (buy → PSA → return)
$
About
Category lists sourced from hobby community research (allvintagecards.com, sportscollectorsdaily.com, psacard.com).
Each category refresh = 3 Claude API calls (~$0.30–0.60). Results are cached for 24 hours per device.