From grimoire
Plans a house hacking strategy to reduce housing costs by renting out part of a primary residence. Covers property types, FHA financing, and rental income calculations.
How this skill is triggered — by the user, by Claude, or both
Slash command
/grimoire:design-house-hacking-strategyThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
Use a primary residence to generate rental income that offsets or eliminates housing costs — building equity while living for free or near-free.
Use a primary residence to generate rental income that offsets or eliminates housing costs — building equity while living for free or near-free.
Adopted by: BiggerPockets popularized the term; the strategy predates it by decades — Franklin and Lincoln both rented out portions of their homes. FHA loans (3.5% down) were explicitly designed for owner-occupied multi-unit properties (up to 4 units), making house hacking an FHA-intended use case. Every major real estate investment course covers it as the lowest-barrier entry to real estate investing. Impact: A house hacker who eliminates $2,000/month in housing costs effectively earns $24,000/year in after-tax income (housing costs are paid with after-tax dollars). Invested alternatively at 7%, $24,000/year for 10 years = $331,000 in wealth — the opportunity cost of not house hacking is enormous. Craig Curelop documented going from negative net worth to financial independence in 2 years using this strategy. Why best: Housing is typically the largest expense for any individual (30–50% of take-home pay). House hacking converts a pure liability into an income-producing asset while using the most favorable financing available (primary residence rates: 0.5–1.0% lower than investment property loans, 3.5–20% down vs. 20–25% for investment property).
Choose the right property type — Options:
Run the numbers before buying — Target: rental income ≥ PITI (principal, interest, taxes, insurance) + maintenance reserve. Ideally: rental income covers 100–120% of PITI → you live free + build equity. Calculation: Purchase price $400k, FHA loan at 7%: PITI ≈ $2,900/month. Duplex: unit B rents $1,800/month. Gap: $1,100/month (still better than $2,900/month housing cost). Unit B rent covers 62% of payment.
Use FHA financing for maximum leverage — FHA allows 3.5% down on 2–4 unit owner-occupied properties. Requires: minimum 580 credit score, primary residence occupancy (you live there), 1-year owner-occupancy requirement. FHA also allows using projected rental income (75% of lease amount) to qualify — helpful for getting the loan approved.
Verify zoning and local regulations — Confirm: is the ADU or rental use permitted by zoning? Are short-term rentals allowed? Some municipalities require rental licenses or limit room rentals. Check before purchasing.
Structure the rental properly — Use a written lease for all tenants (even friends/family). Collect security deposit. Obtain landlord insurance rider (your homeowner's policy excludes rental activity). Report rental income on Schedule E; deduct proportional expenses.
Calculate tax benefits — Rental portion of property generates deductible expenses: mortgage interest (proportional), depreciation (residential: 27.5 years, rental square footage), repairs, utilities (if included in rent). Example: 50/50 split = 50% of mortgage interest + 100% of rental-portion expenses deductible.
Plan the exit — After 1–2 years (required owner-occupancy period), options: (a) remain as owner-occupant, (b) move out and convert to full investment property, (c) sell and deploy into larger investment. The property has accumulated equity + rental income; use it as seed capital for next investment.
Duplex purchase, Denver market: Purchase price: $550k. Down payment (FHA 3.5%): $19,250. Loan: $530,750 at 7%. PITI: $3,800/month. Unit B rent: $2,400/month. Net monthly housing cost: $1,400 (vs. $2,800/month for equivalent rental alone). Year 1: $28,800 rental income. Vacancy reserve (5%): −$1,440. Net income: $27,360. After 2 years: move out, rent Unit A at $2,400. Total rent: $4,800/month. PITI $3,800. Monthly cash flow: +$1,000 before maintenance. Now a full investment property with $19k down.
Finance disclaimer: This skill encodes professional best practices for educational purposes. It is not financial advice. Consult a licensed financial advisor before making investment decisions.
npx claudepluginhub jeffreytse/grimoire --plugin grimoireCalculates maximum home purchase price using the 28/36 rule, stress-testing at rate +2%, and computing total cash needed for down payment, closing costs, and reserves.
Provides mortgage lending knowledge: loan products (conventional, FHA, VA, USDA, ARM, Non-QM), rate structures, underwriting guidelines, compliance (TRID, RESPA, HMDA), and closing procedures.
Calculates home office tax deductions for self-employed: simplified ($5/sq ft, max 300 sq ft = $1,500) or actual expenses (Form 8829) using Wilson transaction tools.