4 blades would be great but 3 blades is fine, stainless would even b better. I'm using a 17p on my boat now but I'm not feeling it. I know a lot of boat shops would lend it to me given that I would buy it from them. I can't afford a brand new prop, I just want to make sure it's what I need before I go find a used one online. I'm in San Jose but works in Alameda and the boat is in Bay Point. so I can pick it up from you. I can leave a cash deposit.