The bare mass spectrometer is the cheapest line in the build and the least useful on its own. Once the rest of the system is priced, a parts build on a current-generation triple quad tends to land above a complete system, not below it.
A bare mass spectrometer appears on the market at a price that looks like most of a complete system for a fraction of the cost. It is the headline number, and it is real. What it is not is a working instrument.
To acquire samples the instrument needs an LC stack in front of it, an ion source, roughing pumps, and a nitrogen supply. Each of those has its own used market, its own condition risk and its own lead time. Priced individually and added up, they routinely close the gap and then exceed it.
On a recent comparison of a current-generation triple quad, a parts build assembled from live listings came in tens of thousands of dollars above a complete system of the same generation, before the software licence and before installation. The direction of that result is the point; the exact figures move with the market and with what is on the floor on any given week.
The first is the wrong-tool bargain. A cheap LC in a listing may be a preparative instrument rather than an analytical one. It is a real HPLC at a real price and it is the wrong front end for a mass spectrometer.
The second is the dead price. A number that looks like the market may come from an expired listing. For some components no live used price exists at all, which means the figure in your spreadsheet is a guess dressed as a comparison.
Where a platform launched recently, its individual modules have not reached the secondary market in any volume. In that case there is no parts route at any budget, and the question answers itself.
We buy and remarket LC-MS, HPLC and GC systems, and handle de-installation, verification and freight.