If you've read The Lazy Man's Refinishing page, you'll see why this is called the Perfectionist's Method and you'll quickly start appreciating the Lazy Man's Method. If you have time and patience, you can give the wood in your trailer the same kind of finish as the piano shown.

You need to start with extremely clean, fresh wood. The entire panel needs to be stripped and sanded. For info on using paint strippers see Windows .

Once you have a clean piece of wood, it's best to start with a stain or a pre-stain. Even if you're going to leave it natural, a mild stain will help even out the grain and create a more pleasing finish.
Just apply with a brush and let dry 24 hours.

Weather you choose to use a water, polyurethane or oil based product, you will achieve a better result if you use the same manufacturer for all phases of your finish. Minwax makes a great line of products.

I prefer polyurethane because I think it leaves a harder finish but they're all good. Many serious pros will only use shellac.

Next you need a sanding sealer. This will keep your finish from soaking in to the wood and will give you the glass like finish without any wood grain or pores showing.
Lightly sand with 340 grit, remove dust with a clean cotton cloth and just apply with a brush and let dry 24 hours.

Next is the clear coat. The trick in getting your finish to look like glass is to apply 3 coats, sanding with a pad in between coats gradually increasing the grit. The pad is simply a kitchen sponge. Just wrap the sand paper around the pad. This eliminates hard spots. Sanding removes imperfections which gives the surface that super flat finish.

Coat 1- Lightly pad sand with the grain, with 340 grit, remove dust, apply with a brush and let dry 24 hours.
Coat 2- Lightly pad sand with the grain, with 680 grit, remove dust, apply with a brush and let dry 24 hours.
Coat 3- Lightly pad sand with the grain, with 1200 grit, remove dust, apply with a brush and let dry 24 hours.
Last- Wet and Dry sand with 1500 grit and a sanding pad (kitchen sponge) . Simply wrap the sand paper around your sponge, dip in warm water and lightly sand in a circular motion.

The final step is to wax it.
You're done. Six days...