  We carried out calculations of the energies, hyperfine structure constants
and electric-dipole transiton amplitudes for the low-lying states of Ba+ in the
framework of the relativistic linearized coupled-cluster single double (LCCSD)
and coupled-cluster single double (valence) triple (CCSDvT) methods. Taking
into account that an iterative inclusion of the valence triples into
consideration is a complicated and computationally demanding process we study
the effects of computational restriction on the final results. We also present
a detailed study of various corrections to all calculated properties and use
our results to formulate several broad rules that can be used in future
calculations of the elements where experimental data are scarce and correct
theoretical predictions are highly important.
