Bob offers his unbiased curmudgeonly service to clients who need a second or unvarnished opinion about the boat they are considering in the used market. Your webmaster mailed off a check to Seattle for just this purpose more than ten years ago. As it happened, we had common interests beyond boats and became very good friends. But, as far as Bob's advice, about which boats would suit my purpose, he was concise and not all hesitant to recommend boats by other designers. Bob will cut through the broker babble and marketing drivel and tell you, that there is no substitute for draft, but he knows that if you sail the Chesapeake Bay, a 7' draft will get you to the nearest sandbar and ultimate upwind performance will have to take a back seat to getting into your chosen anchorage.
Bob's advice is available for $750. That gives you a lifetime of e-mail support with a couple of phone conversations thrown in. Bob will also provide pdf copies of relevant articles, he has written on various technical aspects of boats and performance. The better you can articulate your needs and practical constraints, the more value you will get out of the service. Bob is very, very good at sharpening your focus, but it is a two way street, if you are all over the map and completely unrealistic with respect to what the boat of your dreams will cost, Bob will show his curmudgeonly side until you come to your senses.
If you think the consulting fee is too much, then consider Bob's book: Yacht Design According to Perry as a low cost alternative. It provides a solid primer on many aspects of boat design and will also help you ask better questions, if you do engage as a consulting client.
For the truly frugal there is Cruising Anarchy, where Bob is a frequent poster. Be warned, the language is salty and the restaurant slogan "Tacky, yet delightfully unrefined" describes it well. However, when the conversation stays on track, an awful lot of useful information is available and a couple of collaborative design efforts with Bob as guiding light have taken place on the forum.
Since 1976 Bob has written the monthly design review column in Sailing Magazine where he reviews four boats in each issue. Chances are that the boat you are looking at is in the archive. You can find it here. Bob also writes technical articles for Good Old Boat.