We need to pay our rent!

I've seen this work for other people, but never tried it myself.  I lost my job, and don't have the ability to pay our rent.  I have posted a ton of stuff on Craigslist and OfferUp for sale, but have not any sales yet.  Even if everything that I posted were to sell, I wouldn't have enough money to pay our rent.  If I don't raise the money by 8/5, we will incur a a $165 late fee.  If I don't pay by the 15th, we will be evicted.
Ever since my husband died in 2015, we have been struggling financially.  He had no life insurance & his death was very sudden.  We lost our home, that we had lived in for 17 years, and to say that we have been living paycheck-to-paycheck, would be a generous statement.
My girls are 17 & 20, my 20 year old is disabled, and the thought of her being homeless is really scary.
This is very humbling, but I have heard it said that  one "can't save their face and their ass, at the same time."  This is me, trying to save our asses.  Please help, if you are able!