Development of Power BI Dashboard for procurement and savings analysis

I need to create an interactive dashboard for my work that will display weekly and monthly savings metrics in procurement, as well as allow for price analysis per unit of product across various dimensions: product, supplier, category, department. The dashboard should also compare updated prices with previous periods (e.g., last year or previous contract).

Key Views:

1. Savings Overview:

   • Total savings (€ and %) for the week/month

   • Trend line

   • Year-over-year comparison (YoY)

2. Price Analysis:

   • Price per unit by: Product, Supplier, Category, Department

   • Comparison: current period vs. previous

3. Renewal vs. Historical:

   • Comparison of price in the new contract with last year or previous contract

   • Variation in absolute values and %

4. Supplier Scorecards:

   • Separate page for each supplier (for presentations)

   • Their products, price changes, achieved savings

   • Upcoming planned contract renewals

Key Metrics:

• Unit Price

• Baseline Price

• Renewed Price

• Savings (€) = (Baseline − New) × Qty

• Savings %

• Price Variance (€ / %) vs. LY or previous term

• Volume (Qty), Total Spend (€)

Dimensions / Slicers:

• Date (week, month, year)

• Supplier

• Product / SKU

• Category

• Department / Cost Center

• Contract/renewal status

• Country / Currency (optional)

Comparisons:

• Current period vs. the same period last year

• Before renewal vs. after renewal

• Contract price vs. actual (invoices / PO), if available

Visuals:

• KPI cards (total savings € and %)

• Combo chart (line + columns: trend and YoY)

• Bar chart / Treemap (savings by supplier, category, department)

• Matrix table (product × supplier with prices, deviations, and savings)

• Decomposition / Waterfall (analysis of savings drivers: price vs. volume)

Data Model – recommended tables:

1. Transactions / PO / Invoices

   • date, supplier, product, quantity, unit price, department, category

2. Contracts / Renewals

   • supplier, product, baseline price, new price, start/end date

3. Dimensions

   • Calendar, Supplier, Product, Category, Department

4. Currency table / FX rates, if multi-currency

Other:

• Data refresh: daily or weekly; ability to parameterize date range

• Export: ability to export supplier card to PDF/PowerPoint

Expectations from the freelancer:

• Build a complete Power BI model (Data model + DAX)

• Develop an interactive dashboard with the visuals mentioned above

• Set up refresh (via Power BI Service / Gateway)

• User-friendly filters (UX-friendly)