A junk pickup runs exactly as smoothly as its preparation. None of this is required — crews will haul from wherever things sit — but every step below converts crew minutes into your savings.
Stage what you can

Gather items toward the garage, porch, or curb if you are able; consolidated loads quote tighter and load faster. Can't move it? Fine — just make sure the path to it is walkable: doors propped, hallways clear, dog secured, driveway space for a box truck.
Separate the categories
Donations in one group, scrap metal in another, junk in the third — the sorting you do standing still is sorting the crew doesn't do on the clock. Flag anything with fluids or refrigerant: fridges, mowers, grills with propane. None are problems; all go better announced.
Say the quiet parts at booking
Third-floor walkup, hillside driveway, item heavier than it looks, hoarding-depth room — the crew would rather know than discover. Photos at booking are the single highest-value prep step there is; they turn estimates from ranges into numbers.
Day-of, in Knoxville terms
Summer pickups go early before the humidity peaks; winter ones want the driveway de-iced if it slopes, which here it often does. Be reachable by phone for the arrival window, point once, and let the crew work — most residential pickups are loaded and gone inside an hour.
The one-hour pickup
Staged or at least reachable, categories separated, quirks disclosed, phone answered — that is the entire recipe for the pickup that is loaded and gone before the coffee cools.
Every step is optional, and every step you take is minutes off the clock you are paying for.