Need pics for prep help.

Yes, you will need to strip and brighten for the old stain. Clean and brighten the new wood.

NO stripping of the old stain or sanding?  

See this about new wood.br /> When ready, clean and brighten all wood for the prep and then stain. Stain options are on the link above.

Add pics for prep help.

What is on the wood now is clearly opaque, so yes, you will need a solid stain. As for prep, see this article:

Most of the old stain is gone, so no need to strip. Clean and brighten for prep while pressure washing: For the stain, look at the Armstrong Clar...

No, you have to strip. Plus, what is on your railings looks fully opaque, not semi-trans or semi-solid. You would need to strip the paint here unless ...

Hi Scott; We have an old deck of treated pine. The deck boards are in decent shape. Two years ago we put on a semi-solid (Cabot) deck stain that seem...

@deckstainhelp Thanks! We really appreciate your prompt and knowledgeble reply!