{"id":"life-fl-car-cost-compare","audience":"freelancers","category":"everyday-life","track":"life","technique":"examples","title":"Compare two used cars by three-year cost","free":false,"task":"You're choosing between two used cars and want the full cost over 3 years, not just the price. For each car, add price (including any fees in the fine print), insurance for 36 months and fuel for 36,000 miles at $3.50 a gallon. Get exactly 3 numbered lines in plain text, under 100 words: one per car with the math shown, then which is cheaper over 3 years and by how much. Write a prompt that gets you exactly that.","materialLabel":"The two listings and your notes (attached to your prompt automatically)","material":"LISTING A - Brightway Motors (fictional)\n2021 hatchback, 41,000 miles\nPrice: $14,000 (no dealer fees)\nFuel economy: 30 mpg combined\nInsurance quote (from my agent): $110/month\n\nLISTING B - Cobalt Auto Sales (fictional)\n2020 compact SUV, 52,000 miles\nPrice: $12,500\nFuel economy: 24 mpg combined\nInsurance quote (from my agent): $140/month\nFine print at the bottom of the listing: \"Price excludes $900 dealer preparation fee.\"\n\nMY NOTES\n- I drive about 12,000 miles a year for client visits.\n- Gas around here: $3.50 a gallon.\n- Car B has heated seats, which would be nice.\n- Uncle says SUVs always hold their value better, so B is basically free money.\n- Both sellers say the price is firm.\n- Registration is the same for both, ignore it.","rules":[{"type":"numberedItems","count":3},{"type":"maxWords","max":100},{"type":"plainText"}],"mistakes":[{"title":"Missing the fine print","why":"The AI uses Car B's $12,500 headline price and skips the $900 fee at the bottom.","fix":"Add: \"Include Car B's $900 dealer fee from the fine print.\"","checks":["r1"]},{"title":"Comparing only sticker prices","why":"The AI compares prices and mentions mpg in passing, but never adds three years of gas and insurance.","fix":"Say: \"For each car: price + insurance x 36 + (36,000 miles / mpg) x $3.50.\"","checks":["r0","r1"]},{"title":"No math shown","why":"The AI gives totals you can't check.","fix":"Show it: \"1. Car A: $14,000 + $110 x 36 = $3,960 + fuel $4,200 = $22,160\".","checks":["r0","numberedItems"]},{"title":"Getting a buying guide","why":"The AI adds resale value, features and inspection tips, echoing your uncle.","fix":"Add: \"Line 3 only says which is cheaper and by how much. No advice.\"","checks":["r2","plainText"]},{"title":"Trusting the AI to count words","why":"AI is bad at counting. Ask for \"under 100 words\" and it often lands well over.","fix":"Cap each part: \"each line under 30 words.\"","checks":["maxWords"]}],"promptHints":[{"label":"Includes the dealer fee","patterns":["\\$?900","fine print","dealer (prep|fee)","fees?"]},{"label":"Counts all three costs","patterns":["insurance","fuel|gas","36"]},{"label":"Shows the math","patterns":["show.{0,15}(math|work)","x\\s*36","\\d\\s*x\\s*\\$?\\d"]},{"label":"Sets the number of lines","patterns":["\\b(3|three)\\b.{0,20}(lines?|numbered)"]},{"label":"Sets a word limit","patterns":["\\d+\\s*words","word (limit|count)"]}],"hint":"The cheaper sticker isn't always the cheaper car. Tell the AI every cost to add, where the hidden fee is, and the shape of one line of math.","rubricLabels":["Car A's 3-year cost is $22,160 with the math shown ($14,000 + $3,960 insurance + $4,200 fuel)","Car B's 3-year cost is $23,690 including the $900 dealer fee ($13,400 + $5,040 insurance + $5,250 fuel), with the math shown","Line 3 says Car A is cheaper over 3 years by $1,530 and doesn't bring in resale value, features or advice about which to buy"]}