What a roof inspection costs, and when it earns its price
An inspection is worth paying for when it answers a decision — not as a general health check on a roof you have no plans for.
What you get at different prices
A visual assessment from the ground and a ladder is quick and cheap, and it catches obvious failures. Walking the roof costs more and finds hail bruising, soft decking underfoot and flashing detail that cannot be seen from an edge. A written report with photographs, measurements and an estimate of remaining life costs more again, and is the only version worth having if somebody else is going to read it.
Three situations where it pays
Buying a house, where a general home inspection treats the roof as one item among two hundred and rarely gets on it. After a hail or wind event, where insurers have a filing window and the damage is not visible from the ground. And before selling, where knowing what a buyer's inspector will find lets you price it rather than react to it.
Free inspections
A great many roofing contractors offer an assessment at no charge, and that is a legitimate practice — it is how they quote work. It is also not an independent opinion, and the incentive runs one way. For a purchase or a dispute, paying for an inspection from someone who is not bidding on the repair is the point of paying.
Next step: Roof inspection
Prices vary by property and provider. This page describes what inspections typically include; it is not a price list.