I always strip the wax (dish soap), hit it with iron-x (pulls all the ferrous metals out of the paint), wash, clay, wash, sealant 2x, then finally a top wax coat. It’s a shitload of work but every car I’ve done this too is easy to keep up. The iron-x is really nasty and might be to harsh for single stage paint, it gets brake dust off wheels like magic too.