I calculated time ago as undergraduated and post it at my blog the calculations for traveling through the Universe in a (special) relativist way. At what level and how should we include the effect of cosmological expansion? What if it is not constant? And what to do when reaching the regions where the space expands FASTER than the speed of light?
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The cosmic expansion is approximately $70\mathrm{(km/s)/Mpc}$. Since that is a slow speed compared to the speed of light, you can safely neglect it in intergalactic travel. Only once you travel billions of light years (i.e. if you want to go from one end of the universe to the other...figuratively speaking) does that become relevant. You will have other more relevant problems to consider, notably energy requirements, radiation, and finite time dilation.
Nowhere does space expand faster than the speed of light. That speed is always just those $70\mathrm{(km/s)/Mpc}$ so there are no special regions to worry about.
rfl
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