What It Is

A complete, professional-grade web application for managing every aspect of an automotive repair shop business.

• Technology: PHP + MySQL (no frameworks, pure simplicity)
• Size: 24 files, 11 functional pages, 5,500+ lines of code
• Package: 66 KB compressed, ready to deploy
• Setup: 10 minutes from zero to production
• Cost: Free (just hosting ~$10/month)

Replaces: $2,460/year in separate software subscriptions.

Core Modules (8 Systems)

Database (11 Tables)

• customers — Contact info, email, phone, address
• vehicles — Year/make/model (smart dropdowns), VIN, mileage, color
• work_orders — Service jobs, labor/parts costs, status tracking
• invoices + invoice_items — Billing headers + line items
• tire_quotes — Tire quotations with pricing breakdown
• expense_categories + expenses — 13 pre-configured categories + tracking
• other_income — Non-invoice income (equipment sales, rebates)
• call_logs — Phone call history with timestamps + notes
• sip_settings — Phone system configuration

Design: Foreign keys, cascade deletes, prepared statements (SQL injection proof).

Accounting & Finances

Complete financial management with automatic calculations and professional reports.

• Income Tracking: Auto from paid invoices + manual other income (INC-YYYY-XXXXX)
• Expense Management: 13 categories (Parts, Rent, Payroll, Equipment, Insurance, Marketing, Office, Vehicles, Services, Maintenance, Licenses, Taxes, Other)
• Auto-generated numbers: EXP-YYYY-XXXXX for every expense
• Reports: Profit & Loss statements, category breakdowns, date range filtering
• Dashboard integration: Monthly revenue (green), expenses (red), profit (blue/gray)

Metrics: Total income, total expenses, net profit/loss, profit margin %, expenses by category.

Use case: Tax-ready reports, investor presentations, budget control, trend analysis.

Phone Call Monitoring (SIP Integration)

Real-time call monitoring with automatic customer lookup via SIP/VoIP integration.

• Auto-popup: When phone rings → shows customer name, vehicles, last service
• SIP support: Asterisk/FreePBX (AMI), 3CX (HTTP), Twilio (webhook), Generic webhook
• Customer matching: Auto-match by caller ID (last 10 digits)
• Call logging: Timestamp, duration, status (answered/missed/voicemail), direction (in/out)
• Call notes: Track conversation details + follow-ups
• Phone lookup: Search any number → instant customer + vehicle + service history

Stats dashboard: Today's calls, missed calls, avg duration, SIP status.

Example: Customer calls → Popup shows "John Doe - 2018 Toyota Camry - Last service: Oil change Sept 15" → Answer: "Hi John! About your Camry?" → 10 seconds vs. 3 minutes searching.

Automation & Smart Features

• Auto-generated numbers: WO/INV/TQ/EXP/INC-YYYY-XXXXX (year-based sequences)
• Real-time calculations: Work order totals, invoice tax/subtotals, tire quote pricing, financial profit/loss
• Smart matching: Phone → Customer, Customer → Vehicles, Invoice → Work Orders
• Status tracking: Work orders (Pending → In Progress → Completed), Quotes (Pending/Accepted/Rejected/Expired)
• Caller ID recognition: Auto-match last 10 digits, handles (555) 123-4567 or 5551234567
• Smart dropdowns: Year → Make → Model cascading (250+ models pre-loaded)

Architecture & Tech Stack

Security:

• SQL injection prevention (prepared statements everywhere)
• XSS protection (htmlspecialchars on all outputs)
• Input sanitization (clean_input function)
• Safe delete confirmations

APIs:

• phone_lookup.php — RESTful JSON endpoint for customer lookup
• sip_webhook.php — Receives calls from PBX systems (POST/GET)
• check_incoming_calls.php — Real-time poller (5-second intervals)

Real-World Use Cases

Business Benefits

Installation (10 Minutes)

1. Extract auto-shop.zip to web server directory
2. Create MySQL database: intersysop-dev-mechanic-shop
3. Import database.sql via phpMyAdmin or CLI
4. Configure includes/config.php:

    = "localhost";
    = "your_username";
    = "your_password";
    = "intersysop-dev-mechanic-shop";

5. Access http://localhost/auto-shop/ or http://yourdomain.com/auto-shop/
6. Start using! Add customers → vehicles → work orders → invoices

Optional: Configure phone system (Accounting → Phone Calls → SIP Setup)

Sane Defaults & Best Practices

• Document numbers: Auto-generated yearly sequences (WO-2025-00001, INV-2025-00001)
• Tax rate: 8.5% default (easily changed in invoice page)
• Expense categories: 13 pre-configured (Parts, Rent, Payroll, Equipment, etc.)
• Phone matching: Last 10 digits, handles any format
• Call polling: Every 5 seconds when SIP enabled
• Popup timeout: 30 seconds auto-close
• Vehicle dropdowns: 250+ models from 50+ manufacturers
• Date formats: YYYY-MM-DD (database), "Mon DD, YYYY" (display)

Backup strategy: Daily database exports, weekly full backups recommended.

Documentation (8 Comprehensive Guides)

• README.md — Complete system documentation with usage examples
• QUICK_START.md — 5-minute installation guide
• FEATURES.md — Complete feature overview with technical specs
• UPDATE_NOTES.md — Vehicle dropdown system changelog
• ACCOUNTING_GUIDE.md — Financial system manual (15 pages)
• ACCOUNTING_SYSTEM_ADDED.md — What's new in accounting module
• PHONE_SYSTEM_GUIDE.md — SIP integration manual with PBX configs
• PHONE_SYSTEM_ADDED.md — What's new in phone monitoring

Total documentation: ~40 pages of comprehensive guides, setup instructions, and troubleshooting.

Perfect For

Shop Types:

• Independent auto repair shops
• Small to medium automotive businesses (1-20 employees)
• Mobile mechanics
• Tire shops
• Quick lube services
• Multi-bay service centers
• Fleet maintenance operations
• Auto body shops
• Specialty repair shops

Customer Base: 10-500+ customers, any number of vehicles

Tech Level: Basic PHP/MySQL knowledge helpful but not required

Quick Start Roadmap

1. Day 1: Install system, add first 10 customers + vehicles
2. Week 1: Create work orders, generate invoices, explore features
3. Week 2: Set up accounting, record first expenses, configure categories
4. Week 3: Enable phone system (manual logging or SIP integration)
5. Month 1: Generate first P&L report, analyze call logs, optimize workflow
6. Month 2+: Use data for business decisions, identify trends, grow revenue

Training time: 1-2 hours for staff to become proficient.

Common Traps (and exits)

• "Database import failed." → Check MySQL version (5.7+), charset (utf8mb4), user permissions
• "Phone popup not showing." → Enable SIP monitoring, check JavaScript console, verify webhook URL
• "Customer not matching by phone." → Check phone format consistency, ensure 10+ digits
• "Expenses not showing in reports." → Verify date range, check category assignment
• "Can't create invoice." → Ensure customer has at least one vehicle, check work order exists
• "Smart dropdowns not working." → Clear browser cache, verify vehicle_models table populated

Golden rule: Check browser console + PHP error logs for debugging.

ROI & Cost Analysis

This system replaces:

• Customer management software: ~$30/month
• Shop management system: ~$100/month
• Accounting software: ~$25/month
• Phone call tracking: ~$50/month
• Total: ~$205/month = $2,460/year

Your cost:

• One-time setup: ~2 hours labor
• Web hosting: ~$10/month ($120/year)
• Annual savings: ~$2,340

Time savings: ~5 hours/week in reduced admin work = $10,000+/year in labor savings

Total ROI: $12,000+ in first year

Technical Specifications