Delgan, I'll take a stab at it. I'm thinking this is an American National tricycle from the early 1930s. The style front fender, front rod design, along with the long spring seat are from this time period. American National trikes also sported those rings you see on both front and rear hubs. Take a look at some of the AN trike ads on this page:
http://www.tricyclefetish.com/american_national.php?osCsid=ci2tq4p4ns5eqv0lpoitoc3h25
The Iver Johnson trikes of the era did also have the front rods, but they had a different offset style bend to them and different rear step pads as you noticed. If I could see the shape of the rear step plates better I could be more certain whether it's an AN or not. They had a distinctive shape to them.
Actually, $75 isn't too unreasonable for this one since it is pretty much complete, however I'd think around $50 or so would be fair based on its overall rough condition, missing seat cover and front tire...just my two cents. A lot of sellers are asking way too much for older trikes in fair to poor condition these days, which has kept me from buying any more. This seller is at least being a little more realistic in price.
Dave