Everything worth reading here is on the page for the thing itself.

Where a key rotates its whole sweep and the door still refuses to shift or fasten, the lock is fine — it is doing precisely what it was made to do. The change is structural. Hinges have let the leaf drop, a wet season has fattened the timber, heat has grown the frame, or the strike has wandered off the bolt's path. All of that wants realigning, and paying for a cylinder to cure it is among the commonest wasted purchases in Cape Town.

A key that rotates halfway and jams has met an obstruction: grit, lubricant gone to varnish, a component that has given up, or a blade worn away from its original profile. Fish out the oldest key you own and try that before concluding anything. Duplicates made from duplicates mimic a dying cylinder extremely well, and one cut back to specification quietly resolves faults people have tolerated for a year. Filed under lock repair, not replacement.

A key that refuses to go in, or goes in and will not move, means the mechanism has genuinely seized — and that is where skill at opening things actually pays. Of the three, it is also the only one where a drill is ever the straight answer: following an inspection, described to you first, and never as the opening move. Emergency door opening sets out the whole argument.

A main entrance faces a road, sits in view of passers-by and has generally had more attention paid to it than anything else on the plot. The openings round the back have had none. Rank your ways in by how long somebody could stand at each without being seen, and the budget reorganises itself — normally to something smaller than you had in mind.

The next one is spending on the mechanism when the timber around it is what gives. Break-ins on houses mostly end with the strike plate pulled clean out of soft jamb, the cylinder untouched and entirely blameless. Packing that frame and driving fixings into something structural raises the effort required by more than a better lock would, for less money. Security lock upgrades works through it properly.

The third is ironmongery bought while the real gap is who holds a key. Nobody breaks in through something they can open, so where the number of keys is a mystery, every mechanical improvement addresses a threat you are not facing. Turning that mystery into a figure costs less than most hardware and belongs at the front of the queue; see lock change services.

With doors, what separates one price from another is groundwork rather than the product. Splits get filled, jambs packed, keepers strengthened, somebody's earlier botch undone — hours of labour that disappear the moment they are finished. A figure with none of it priced in either belongs to a doorway in genuinely good order or to a job that intends to skip the stage. One question settles it: what exactly is this being anchored into, and does that need attention first?

With cars, the manufacturer sets the price rather than the tradesperson. Certain immobilisers accept an additional key without fuss; others enforce a waiting procedure that nobody can shorten. Two vehicles quoted very differently is ordinary. One vehicle quoted very differently by two people deserves a blunt question about scope — above all, whether keys nobody can account for are being wiped. Car key programming covers it.

Where a suburb changes the answer — and it often does, since salt, wind, winter damp and inland heat each destroy hardware differently — the relevant page sets that out for the specific area rather than in general terms. And on any job, be wary of a firm figure offered before anybody has heard what is actually wrong. A lockout on a modern cylinder and a lockout on a jammed multipoint door in a swollen frame contain different amounts of work. What you should expect instead is a clear account of what the cost depends on, and a settled number once somebody has looked at it.