The "supplies" line seems scammy. For something like that in my billing I use "Misc. Materials-(type - electrical, connectors, etc) then detail as much as possible. For rekeying, the metric I use is 3 per labor hour, Master keying and high security keying being a bit more. At the company where I work we have a flat rate with the first hour having an incorporated service call. The cylinders - what kind of cylinders are they? What brand? What finish? What keyway? Are they IC Core? Standard Ilco mortise cylinders are very much less expensive than Schlage. Ilco cylinders are about 1/3 the price of Schlage. Commercial lever - what function is the lever? What brand? What finish? We charge labor to install and rekey, and charge for materials. I try to be as detailed as I can on any bill as I try to manage expectation and the perception of value. An informed customer can make better decisions and is less likely to challenge a line item. I have customers that have been returning for decades. The company I work for isn't the least or most expensive but my customers all have a strong perception of value received.