The Fantasy Rent Number: Rental rates should be based on what similar properties are actually renting for RIGHT NOW — not aspirational listings sitting vacant for 3 months. The Invisible Expenses: Beyond mortgage+taxes+insurance: maintenance reserves, management fees, capex reserves, landscaping, pest control, legal, accounting. The Leverage Trap: 70% LTV survives a 20% drop. 90% LTV goes underwater with just a 10% drop. 95% LTV is destroyed by a 5% decline. Speed Over Safety: Urgency is almost always manufactured. The properties that look like the best deals are often priced low because they have problems. Running on Empty: Without cash reserves, any common scenario forces a distressed sale. Keep 3-6 months of expenses per property in reserve.