The clean house scares me more than the ugly one
An ugly house usually tells you what you're buying. The one that makes me nervous is the house that looks finished but has a converted garage, bonus room, added bathroom, or finished basement that doesn't match the tax records. It may rent well and photograph well, but if the appraiser or lender doesn't count that space, the BRRRR can fall apart at the refinance.
Which would you rather buy: an obviously rough house with a clear scope, or a cleaner house with questionable permits and square footage?