What does the なのに mean in this sentence from Makino and Tsutsui's A Dictionary of Advanced Japanese Grammar:
アパートの家賃を払うのが精一杯なのに、まして(や)家を買うなんて夢物語だ
Dictionary of Advanced Japanese Grammar translation:
"I am just managing to pay the rent for my apartment; how much more of a dream it is to imagine buying my own house!"
This entry is teaching まして which I understand, I fathom that the なの is simply used for emphasis, and the に in its use as a sentence final to indicate sympathy or regret (Dictionary of Intermediate Japanese Grammar p. 234). Am I right in thinking this or is it something else?
Many thanks in advance :)