Dad will say the front steps have been fine for thirty years. Agree with the part that is true, then ask him to watch one person pull on a rail that has not been anchored yet. A porch rail is its own install, separate from any stair handrail inside the house, and it fails at the anchors more often than at the post.
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Walk the steps first
Measure the rise and the run of each step, note where the landing sits, and check whether the steps are poured concrete, brick, or stone over a block core. Decide where the rail starts and stops and whether it needs a return at the top so a hand has somewhere to land. Mark each post and anchor point with painter's tape before anyone drills.
Ask the installer three things in writing
Ask which anchor goes into which material and how deep it reaches solid block or concrete rather than mortar joints or a thin veneer. Ask which height and grip size the rail is built to meet and which local code applies at your address. Ask who patches the drill holes and what the patch looks like after a winter of freezing and thawing. If the installer cannot answer the first question in plain terms, get another quote.
Set the anchors, then the rail
Drill to the depth the anchor label lists, clean the hole, set the anchor, and let it cure for the full time printed on the packaging. Do not hang the rail on anchors that are still curing, even if the crew is on site and ready to move. Set the posts plumb and the rail at the pitch the design calls for.
Pull-test before anyone leans
Have the installer pull hard on each post and each anchor in the direction a falling person would pull. Then push down and sideways at the top and at the midpoint. Any movement at an anchor means the job is not finished. Have the installer redo that anchor rather than tighten a nut and call it done.
Keep the install record
Photograph the anchor locations before any cover plates go on, save the product labels, and keep the installer's name and number where you will find them. You will need them the first time a bolt backs out.
Next move tonight: walk the front steps with a tape, write down the rise and run of each step, and send the installer a photo of the masonry with one question about anchor depth.