I think you also need to consider what you're asking the flooring specialists (sales, installation, whatever...) to do. Are you asking them to recommend/sell/install the flooring with a warranty or assurance you can come back to them if the wood moves? I assume the original flooring guy that said he wouldn't install planks wider than 4.5" meant he wouldn't install them and back them with any kind assurance. Maybe he wouldn't install them under any circumstances because he's worried you'll drag his name through the mud if they cup/warp. Even if they inspect your site, how do they know you'll take the proper steps to control the humidity levels in both summer and winter? How do they know how "sensitive" you are to the inevitable gaps and minor cupping. This was much the same discussion we had with our granite counter top dealer. If you want a perfect, uniform look, go with an engineered product. Natural stone has imperfections. Embrace it or pick something less natural. Same with wood flooring. The wider the plank, the more susceptible to movement in all directions. It's easy to get someone on a message board to say they'll be fine with 10" wide planks. They likely understand the installation and maintenance requirements and, most importantly, don't have to worry about you suing them later if you're unhappy with your choice.

Since my husband and I recently went through this DIY, I can make a few suggestions, although we didn't refinish, we installed unfinished rustic inexpensive red oak floors ourselves and finished them. I don't know anything about removing a wax finish, maybe someone here can advise or you could try a different hardwood flooring forum. For the sander we rented a U-sand, which is a floor sanding machine that is supposedly made for the DIY'er. It worked great, got right up to the edges and was really easy to use. I don't know how well it would perform for refinishing, as that involves more sanding. For the stain and poly, we went with the professional grade stuff. It was so worth the extra money as the products were much more forgiving to work with, and I think will have better long term durability. We went with the Bona products which are designed for hardwood floors. We`used the Bona Drifast stain, which is an oil modified stain that dries quickly. The stain is very rich looking and was wonderful with any accidental overlap. We mixed a couple different colors for a custom stain color. We went with the new Bona waterbased Traffic HD in the extreme matte finish and I love it. I think the traffic HD has one of the highest durability commercial ratings. A matte finish will hide more imperfections and scratches than a shiny finish. Although it says extreme matte, the finish does have a slight shine with a very natural wood look, it looks great with our rustic grade floors. I've never seen a poly finish like it, it's so velvety smooth and natural looking. It's sheen is in between Bona Naturale and Bona Traffic Satin HD. The water based polys I believe are more durable than the oil base and this one is meant to go on top of Bona's oil base stain. The Bona waterbase poly also had very little fumes that disappeared with in a couple days. It has a separate catalyst (hardener) that has to be added and then you have 4 hours once you add the hardener in. We were concerned at first, but with the T-bar applicator, we were able to get one application done in about 45 min-1 hour (650 sqft+ stairs). We have two dogs who like to race around the house and hate to have their nails clipped, I have yet to see a scratch, this finish seems to be wearing like iron, I am so impressed. We applied the stain, waited 48 hours, then applied the first coat of poly, the next day we buffed it, wiped down with a damp cloth, let it dry and then applied the second coat and let it fully cure. We bought the T-bar poly applicator, which worked out well. We also bought the Bona Mixer bottle, so we could mix smaller batches when we needed to and didn't have to mix up a whole bottles worth. This was 7.00 well spent as we mixed up a gallon and a half for each application. For wood filler we tried Woodwise floor filler, and Timbermate, I thought the Timbermate performed a little better, but both products were much better than anything at Lowes, or Home Depot. The waterbased wood fillers are great because wiping off excess with a damp rag is fairly easy, even after it's dried. Plastic putty tools should be used with the waterbased fillers as some metal scrapers can discolor the filler. Since the Bona products are professional grade, we bought them through a company that sells to the general public and professionals. Their business is mostly an online store, but people can come in and buy products from them locally. Since they were local for us we got to talk to them in person. They were great, they took the time to answer all our questions each time I stopped in for products. I found them extremely knowledgeable and very caring, their how to videos on their website were also helpful. Floor Mechanics Online Store We spent about 1,750.00 total for 1,000 sqft of very rustic red oak flooring, Pneumatic floor nailer, moisture meter, sander/buffer rental, and finishing products. It was some work, but worth it for site finished, solid hardwood flooring. Good luck with your son's floors.

bmorepanic, I just love those words, scalawags and varlets! Not sure why you chose them, but never mind, they have such character... Reminds of when my son was learning to talk and said "I like the word NASTY!" LOL. I just wish I could use such colorful language and have it come out right. Seems like when I do, people take offense! :) Sorry, not meaning to interrupt your post on wood floors. I am reading it myself, because though the finish on my floor lasted just fine in bedrooms, the kitchen didn't and I need to know a good finish too!

I think you can have solid...just work with a narrower plank. The cut is also important. Some cuts are much more stable than others. Rift sawn lumber is more dimensionally stable (and more expensive) than other cuts. I would personally look for a narrow plank (more stable + cheaper installation costs) in a Rift Sawn presentation (most dimensionally stable + more expensive). I would guess you would end up spending about the same amount this way. Yet you get a more stable wood with fewer problems in a home without the added stability of humidity control. Of course you can move to engineered to avoid SOME of these concerns...but even engineered has limits re: humidity control (or lack there of).