Carver 404 Swim Platform Weight Limit?

If the factory can't tell you, how would you expect someone here to give you a specific number? I would think guesses and ballpark are the best available without perhaps a surveyor examining you boat up close and calculating and even then he's just doing an estimate.

Assume he meant Carver/Marquis?

They're usually hung on davits so you can launch it and retrieve it. Not sure how you're going to keep a dingy on the dive platform without some type of chocks.

If you look on Yachtworld you'll see how most 404's do it. There are several with davits mounted on the platform and 10' Rib's with 10-15 hp. Some do seem to sit low in the back when underway but perhaps that smooths out. Saw one with a Seawise Hydraulic davit system (it had a 12' AB), another with St. Croix. Still checking your mounting and your transom in advance and making reinforcements if needed is advisable.