If your house has seen better days and you want to sell it without investing in renovations, then you can slash its price and put it up for cash. Nothing says, "I want to sell my house fast" or "I want to sell my house for cash" than a property that's up for grabs for prospective buyers.
The least you can do is to ensure your house is presentable for a walkthrough; some people buy property to renovate, so they won't mind the grime on the kitchen sink or the loose shingles on your roof. It's difficult to find cash buyers on your own, though; hire reseller agents to do the legwork. You have to pay for the service, but the cost is trivial once the viable offers come in.
Now if looking for an agent is too much of a hassle for you, you could try bringing your business to companies that will offer cold cash for your house. Yes, there are such companies nowadays, and the great thing about them is they release cash payment for houses they buy quickly. You no longer have to wait long or go through a stringent collection of paperwork. Use the Internet to look for these companies. There's no harm in trying out the service of a "house for cash" company.