I recommend making the changes yourself, unless it is something that requires personal taste (paint and carpet are the biggest examples). While some buyers might see needed repairs as an opportunity to save a little, most buyers will see it as a potential headache.
More importantly, as Jamie already pointed out, the first impression is important. People can be turned off by the smallest things, including a pile of laundry in the bedroom, toilet seats up, or a cluttered kitchen counter. Making the repairs ahead of time won't always result in a dollar-for-dollar return but it can make your home more marketable and result in a sale.