{"id":"dat-free-lens-buy-vs-rent","audience":"freelancers","category":"decisions","technique":"context","title":"Decide whether to buy or rent a lens for a year of shoots","free":false,"task":"You expect about 15 shoots next year that need a telephoto lens. If you buy, you'd resell it after a year for about 60% of the price. Write exactly 2 numbered lines: 1) buy = price − resale, 2) rent = shoots x rental fee, each with the math, then one unnumbered last line: Buy or rent: [choice], saves $X. Plain text, under 60 words.","materialLabel":"Lens prices you found (attached to your prompt automatically)","material":"70-200mm f/2.8 LENS - options (for event + sports shoots)\n\nBuy new (Northlight Camera): $1,200\nBuy used (excellent condition): $950, no warranty - skipping this one\nRent (Lensbox, per shoot, 3-day rental): $60\n\nNotes:\n- Used prices for this lens hold up well; resale listings run 55-65% of new.\n- Insurance rider for owned gear: my policy already covers it at no extra cost.\n- Lensbox has had stock problems on busy weekends.\n- 2 of my clients are high school sports teams (fall and spring seasons).\n- My friend says \"renting is always cheaper.\" Not checked.\n- Tax stuff: ask my accountant, not part of this.\n- I shoot about two events a month.\n- Shared with the team in the usual folder.","rules":[{"type":"numberedItems","count":2},{"type":"plainText"},{"type":"maxWords","max":60}],"mistakes":[{"title":"Not giving your shoot count","why":"The AI can't compare without knowing how often you'd rent.","fix":"Add: \"About 15 shoots next year.\"","checks":["r1","r2"]},{"title":"Forgetting resale","why":"The AI treats the full $1,200 as spent.","fix":"Add: \"Resale after a year is about 60% of the price.\"","checks":["r0"]},{"title":"Not asking to see the work","why":"You'll want to rerun it with different numbers.","fix":"Add a line to copy: \"1. Buy: $1,200 − $720 resale = $480\"","checks":["numberedItems","r0"]},{"title":"Trusting the AI to count words","why":"AI is bad at counting. Ask for a total word limit and it often lands over it.","fix":"Cap each line: \"each line under 12 words.\"","checks":["maxWords"]},{"title":"Forgetting where it goes","why":"AI loves markdown tables and bold, which show up as clutter in your gear notes.","fix":"Add: \"Plain text, no bold, headings or tables.\"","checks":["plainText"]}],"promptHints":[{"label":"Gives your shoot count","patterns":["15 shoots|15 times","how (often|many)"]},{"label":"Mentions resale","patterns":["resale|resell","60\\s*%"]},{"label":"Asks to show the math","patterns":["show (the |your )?(math|work)","x \\$|\\bx\\b.{0,10}=","calculation","step"]},{"label":"Sets a word limit","patterns":["\\d+\\s*words","word (limit|count)","under \\d+"]},{"label":"Asks for plain text","patterns":["plain","no bold","no markdown","no formatting","no (headings|tables)"]}],"hint":"The answer depends on how often you'd use it and what you'd get back. Give the AI both.","rubricLabels":["Buy is $1,200 − 60% resale ($720) = $480","Rent is 15 x $60 = $900","The last line says buy, saving $420, with nothing before the first numbered line"]}