Everyone who has listed or considered listing their space on Airbnb, VRBO, HomeAway, or any number of other vacation rental sites knows the thought. "What should I write? How much should I say?"
My first piece of advice is to keep it simple - as much as you want to write paragraphs upon paragraphs to win your potential renter over, don't. The average renter will read no more than the first 2 sentences to a paragraph before moving on to the next listing.
My second piece of advice is to be careful what you leave out. Does your neighborhood look scary, but is actually safe? Include that. Is your rental super small? Include that in your listing description as well. How you say it is also important - don't make it worse than it is. You may scare away some potential renters, but that's ok - they wouldn't have been happy anyway - and a bad review is much, much worse than a brief gap in rent.
I really recommend going through the process yourself - whether or not you actually end up staying in a vacation rental. Look at what other homeowners write, and think about what makes you feel most comfortable.
If all else fails, have a (trusted) friend review your listing. A second opinion goes a long way.