  Most cosmological data analysis today relies on the
Friedmann-Lemaitre-Robertson-Walker (FLRW) metric, providing the basis of the
current standard cosmological model. Within this framework, interesting
tensions between our increasingly precise data and theoretical predictions are
coming to light. It is therefore reasonable to explore the potential for
cosmological analysis outside of the exact FLRW cosmological framework. In this
work we adopt the general luminosity-distance series expansion in redshift with
no assumptions of homogeneity or isotropy. This framework will allow for a full
model-independent analysis of near-future low-redshift cosmological surveys. We
calculate the effective observational 'Hubble', 'deceleration', 'curvature' and
'jerk' parameters of the luminosity-distance series expansion in numerical
relativity simulations of realistic structure formation, for observers located
in different environments and with different levels of sky-coverage. With a
'fairly-sampled' sky, we find 2% and 15% cosmic variance in the 'Hubble' and
'deceleration' parameters, respectively, compared to their analogies in the
FLRW model. On top of this, we find that typical observers measure maximal
sky-variance of 7% and 550% in the same parameters. Our work suggests the
inclusion of low-redshift anisotropy in cosmological analysis could be
important for drawing correct conclusions about our Universe.
