Whatever refinishing method you choose, know that moisture invites organisms into the wood that cause it to rot over time, so remove and clean up anything that is allowing water to collect in parts of the deck. Also, repair anything that may be habitually splashing water onto the deck, such as a leaky hose spigot.
To winterize, clean your deck of debris and remove and store your outdoor furniture in a dry place. Leaving your furniture out during the wet winter months can cause it to wear down more quickly.
You will likely need to hire a carpenter or contractor to help you design and install new railings, because they consist of detailed parts and connections. Have an idea of the railing type you want installed, and ask for product and design recommendations from the professional you hire. Also, check that your preferred railing type meets local codes before having it installed.
Keep water from pooling under your containers by placing a saucer beneath them to collect excess water or raising the containers off the deck.
Be aware that large containers can add a significant amount of weight to the deck, so it’s best to locate large, heavy containers over structural beams. Always consult a professional if you are unsure of your deck’s weight capacity.