Visuals shouldn't be too bad so long as they look nice and you offer them at fair prices. You won't need paperwork since you're talking about visual morphs. It's a good idea to stick with dom/co-dom while you build up your reputation - you probably wouldn't be able to sell recessive hets as anything other than "normals" until you've been around a while. Don't let this disuade you from getting into recessive gene animals if that's what floats your boat, just be prepared to keep all the hets or take a major dive when selling them until you've been around a while and built up some positive customer feedback/trust.