To-day or to-morrow - as if ye had the free choice of either day as a certainty. Others read, “To-day and to-morrow.”
such a city - literally, “this the city” (namely, the one present to the mind of the speaker). This city here.
continue ... a year - rather, “spend one year.” Their language implies that when this one year is out, they purpose similarly settling plans for to come [Bengel].
buy and sell - Their plans for the future are all worldly.