Determining the offer price for a property is part art and part science. The most sensible, offer price to use is the one that most lenders (who will fund the deal) will use, and that's the current market value as determined by the appraisal. However, in most cases you'll present an offer before ordering an appraisal or inspection. So, you should start of with making an offer close to the current market value as determined by the recent, sold comps, and you can readjust your price from there if necessary (after having processed the results of your appraisal and inspection).
Ignore all of that nonsense about discounting the list price by X%, because it's not enough in some cases, and it's too much in other cases.