This is pretty simple, IRS pub 527 (http://www.irs.gov/publications/p527/ar02.html#d0e2480) provides a table for determining what items in your rental may be depreciated and over what period (see table below). Simply estimate the actual value of these items when you place the rental in service instead of paying someone several hundred to a thousand bucks for a Chattel appraisal.
It’s not rocket science.
A large landlord might have someone appraise these items, but my guess is that most simply evaluate a few types of their units and count how many A/C units dishwashers, etc they have in their buildings and do some multiplication. These items are also constantly being replaced. Once you replace (as many large landlords do constantly) the basis is what you paid, so no appraisal is needed in those cases.
IMO the market for selling these appraisals is to large property owners (who likely have the skills and manpower to do their own appraisal) and newbie landlords who don’t yet know the rules.
