price-predator

Price Predator

Track product prices across time and stores, get alerts on price drops, and predict the best time to buy.

Quick Start

# Track a product with its current price
python3 scripts/price_predator.py track --name "Sony WH-1000XM5" --price 350.00 --category electronics

# Record a new price observation
python3 scripts/price_predator.py update  --price 299.99

# View ASCII sparkline price history
python3 scripts/price_predator.py history 

# Check for price drop alerts (all products)
python3 scripts/price_predator.py alert

# Check best time to buy by category
python3 scripts/price_predator.py best-time --category electronics

# Full report
python3 scripts/price_predator.py report

Commands

How It Works

• Database: JSON file (~/.price_predator_db.json by default). Override with --db.
• Price tracking: Each update records price + timestamp + source. Build a history over time.
• Alerts: When the latest price drops more than the threshold (default 10%) below the median of all recorded prices, an alert fires.
• Seasonal prediction: Uses a built-in calendar of best months to buy each category (see references/seasonal-buying-calendar.md).
• Depreciation: Category-aware annual depreciation rates provide a rough price prediction model.

Category-Aware Patterns

Price Predator knows seasonal discount windows for 15+ categories:

• Electronics / TVs / Laptops → Black Friday (Nov), Cyber Monday
• Mattresses → May (Memorial Day), February (Presidents' Day)
• Appliances → September (Labor Day), May (Memorial Day)
• Smartphones → September (new model launches), November (Black Friday)
• Furniture → January & July (inventory clearance)
• See references/seasonal-buying-calendar.md for the full calendar.

Options

• --db — Use a custom database file (global flag, before subcommand)
• --target — Set a target buy price when tracking
• --threshold — Set alert threshold as a fraction (0.15 = 15%)
• --category — Set product category for seasonal predictions

Files

• scripts/price_predator.py — Main script (Python stdlib only, no dependencies)
• references/seasonal-buying-calendar.md — Best months to buy each category
• references/price-tracking-strategies.md — Strategies for effective price tracking