My elderly dogs simply wouldn't walk up a ramp (unless it was so stoutly-built that it was impossible to use). I found they were happier being helped up the steps using a "handle" (simply a wide fleece-covered band that went around their chest, with a handle on the top) My late Aussie would wait at the stairs for me to "put his handle on". And MY level of effort wasn't really all that much - I wasn't carrying him, just giving some stability and forward motion.
Ed, Deb, and 2 dogs
Looking for a small Class C!