Line 1: The filter line
Start with the facts that eliminate unfit inquiries.
Tenants who don't fit self-select out before you get a call from someone with a Great Dane.
The unit
Square footage, layout, and light. "South-facing with floor-to-ceiling windows" is specific. "Bright" is not. Include laundry status (in-unit washer/dryer is a major filter), parking specifics, and any included utilities.
The building and neighborhood
Name the transit line and walking distance. Name the grocery store. Give commute times to two major employers. "12-minute walk to the Blue Line, Whole Foods on the corner, 25 minutes to downtown by train" tells a whole story in one sentence.
The deal terms
"12-month lease, first month + 1.5x security deposit, income requirement 3x rent" — this separates serious inquiries from time-wasters. Be explicit. Vague terms attract low-quality applicants.