Among those taking part in the general strike was Gonzalo Álvarez, 27, who was visiting different picket lines in central Madrid.
Although he works in sales, he has been volunteering for a housing union that tries to protect tenants and makes them aware of their rights.
The eviction of Maricarmen Abascal at the end of September “was the little fire” that sparked this protest, he told the BBC.
Álvarez knew the 87-year-old, who had faced a tripling of her rent under new landlords, and says he was deeply upset by her treatment.
He rents a small, one-bedroom flat with his girlfriend, a dental hygienist, in the city’s southern Arganzuela disrict. The couple pay €1,000 between them, which means each spends about half of their salary on housing, even before other bills.
“It’s absolutely crazy… with the food, with the electricity, with the water, with gas.”
He sees no way of getting on the property ladder: “You have to collect an insane amount of money to be able to buy a house. So with these salaries, it’s impossible.”
With current rent and purchase prices, he believes buying somewhere is “completely impossible”.
However, the vice-president of the CEOE, Spanish biggest business association, Miguel Garrido, criticised the strike, complaining that businesses had little to do with the price of housing.
“This is not a strike for labour-related reasons, but rather for political ones, and it is closely linked to the early calling of elections,” he said.
Demonstrations were planned for some of Spain’s biggest cities later in the day and the scale of support will be widely viewed as an indicator of public discontent ahead of the election.
Another reliable indicator of support for strikes is the level of demand for electricity with Spain’s industrial sector.
Power usage in Spain fell by 7.5% during the early hours of Wednesday, according to data from operator Red Eléctrica. During the last general strike 14 years ago, equivalent consumption was down by more than 15%.