We discuss short-baseline electron and muon neutrino disappearance searches into sterile neutrinos at a very low energy neutrino factory (VLENF) with a muon energy between about 2 and 4 GeV. A lesson learned from reactor experiments, such as Double Chooz and Daya Bay, is to use near and far detectors with identical technologies to reduce the systematical errors (the VLENF has been recently renamed into nuSTORM-Neutrinos from STORed Muons). We therefore derive the physics results from a combined near-far detector fit and illustrate that uncertainties on $\mathrm{\text{cross sections}}\times \mathrm{\text{efficiencies}}$ can be eliminated in a self-consistent way. We also include the geometry of the setup, i.e., the extension of the decay straight and the muon decay kinematics relevant at the near detector, and we demonstrate that these affect the sensitivities for $\Delta m^2\gtrsim 30{\mathrm{eV}}^2$, where oscillations take place already in the near detector. Compared to appearance searches, we find that the sensitivity depends on the locations of both detectors and the muon energy, where the near detector should be as close as possible to the source, and the far detector at about 500 to 800 m. In order to exclude the currently preferred parameter region, at least ${10}^{19}$ useful muon decays per polarity are needed for $E_{\mu }=2\mathrm{GeV}$, or, alternatively, a higher muon energy can be used.

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