Alexseal is repairable, OP is talking white so that makes it a lot easier. What use to be common is to paint the house with Awlgrip which is not repairable and the hull with Awlcraft, which is an acrylic urethane and is easily repairable but not quite as durable as Awlgrip. The thought was that the hull gets beat up, banging into docks and such, more than the house, so make that repairable.
It's impossible to determine what the cost would be as everyone has different expectations. Ballpark, if you want to have a professional do a professional repaint of the whole boat, take it all apart and put it back together again, it's going to likely be around $1k/ft. But it is a 32 year old boat, chances are you're going to find unexpected things that will drive the cost up from there. And you might be adding yard costs. And those freakin' black anodized Bayliner window frames that are now all faded and are going to look lousy against the shiny new paint so you'll want to paint those also, which is a surprising amount of work.
I've re-gelcoated a couple of smaller boats. I can't even imagine how expensive it would be to do a boat this big, you're talking serious expensive. You'd have all the same prep that you'd have with paint. But instead of just spraying topcoat and it's all shiny you'd add massive hours of wetsanding, buffing and polishing to get it shiny. I doubt if 2X the price of a paint job would do it and you'd end up with an inferior finish to paint, it would not be as shiny or as durable. Gelcoat sprayed in the open just isn't the same as done in a mold, don't care what anyone else says.