I would not work for a company that would have me work from home for 10% less than what I make now. Why would I do that? I am paying more by working from home since I need to supply my own utilities and resources just to do my job.
On the contrary, you likely have lower commuting costs.
However, the more important aspect might be that you end up needing more space at home and the employer needs less space in the office. Working from your kitchen table is probably not the best idea in terms of ergonomics.
In my opinion this aspect gets few attention in the discussion.
Many couples do not have two spare bedrooms (especially in the Bay Area) to work in. That means potentially renting/buying a larger living space, or converting living space into working space.
N=1, but my lower commuting costs are more than offset by the lack of company-provided lunches, snacks, and coffee.