  Sequestering is a promising mechanism in 4D string models to reconcile
high-scale inflation with low-energy supersymmetry. In this scenario the MSSM
lives on branes at singularities and it is sequestered from the sources of
supersymmetry breaking in the bulk. The soft-terms are suppressed with respect
to the gravitino mass so that all moduli are heavy enough to avoid any
cosmological moduli problem. In this paper we study stability bounds and
flavour constraints on sequestered string models, finding that they can be
satisfied if the soft-terms give rise to a mass spectrum typical of split
supersymmetry with TeV-scale gauginos and sfermions around $10^7$ GeV. When
instead scalar and gaugino masses are of the same order of magnitude, large
flavour changing neutral currents can be avoided only by pushing the soft-terms
above $10^6$ GeV. However this scenario is in tension with stability bounds due
to the presence of charge and colour breaking vacua which could be populated in
the early universe, and the possible emergence of directions along which the
potential is unbounded from below.
