Case Study: Sarah’s First Investment Portfolio

Sarah, a 29-year-old UX designer, sets a goal to save $65,000 in 7 years for a home down payment. With a moderate risk profile, she builds a simple 60/30/10 portfolio of global equities, bonds, and cash. By investing $550/month via a low-cost platform and rebalancing annually, Sarah stays on track, growing her portfolio while building strong investing habits.

7/22/20251 min read

person holding pencil near laptop computer
person holding pencil near laptop computer

Case Study: Sarah’s First Investment Portfolio

Profile

  • Name: Sarah Lee

  • Age: 29

  • Occupation: UX Designer

  • Annual Income: $60,000

  • Goal: Buy a home in 7 years

  • Target Amount: $65,000 for down payment

  • Monthly Savings: $550

  • Risk Tolerance: Moderate

  • Investment Knowledge: Beginner

Step 1: Defining the Goal

Sarah wants to save $65,000 over 7 years. With $550/month saved and assuming a 5–6% average annual return, she’s on track.

Step 2: Portfolio Allocation

Based on her moderate risk tolerance, Sarah's starting allocation looks like this:

Asset ClassAllocationExample InstrumentsGlobal Equities60%Vanguard Total World ETF (VT)Intermediate Bonds30%iShares Core US Aggregate Bond (AGG)Cash / Money Market10%Fidelity Government Money Market Fund

Step 3: Investment Plan

Sarah invests through a low-cost robo-advisor platform. Her key actions:

  • Sets up automatic monthly contributions of $550

  • Chooses a taxable brokerage account

  • Rebalances annually to maintain 60/30/10 mix

Step 4: First Year Review

After 12 months:

  • Her portfolio grows 6.2%

  • Equities rise to 65% due to tech rally

  • She rebalances back to 60/30/10

  • She increases contributions to $600/month

Takeaways for Beginners

  • Set time-bound goals to guide investment strategy

  • Diversify across global stocks and safe bonds

  • Rebalancing keeps risk in check

  • Consistency beats timing, automate and remain invested