Good afternoon, Larry,
Thank you for submitting photographs to Mearto for appraisal.
I've looked through numerous artist databases and can not find a conclusive match, though this could be by the Hungarian artist Maria Modok (1896-1971), whose style is similar to that in which your painting is done.
With the lack of a more definitive attribution, and to be on the safe side, however, I am calling this:
Abstract Continental school, mid 20th Century
Urban landscape, signed indistinctly lower right, dated x-x-63, oil on masonite panel, 37 x 28 inches
$500-700 is in line with what paintings of similar size, vintage and composition are bringing at auction within the last 2-3 years.
I hope this information is useful to you, and apologize I was not able to make a definitive attribution for you. Please let us know if you have additional items to appraise, and thank you again for using Mearto.