I am about to install unfinished hardwood flooring in an apartment that I
will be renting out. I went around and around trying to decide whether to
go with prefinished or unfinished hardwood etc. In the end, I think I
probably made the wrong choice. But, I already bought the unfinished
hardwood, and now I need to just go forward with it and hope for the best.

It's a 440 square foot area that will be getting the new hardwood. I bought
about 480 square feet of #2 red oak 3/4-inch unfinished hardwood to allow
for waste. The room is over top of another apartment, so I don't need a
vapor barrier. The new unfinished hardwood is actually going on top of an
old hardwood floor that I decided not to try to have refinished. The whole
apartment was redone, including all new doors and new kitchen and bath
ceramic tile floors (which raised them up), so adding the new hardwood floor
on top of the old one won't be a problem in terms of the added height to the
floor. The plan is to put down red rosin paper and then nail down the new
unfinished hardwood. The new hardwood will be going down so it will be at a
90 degree angle to (meaning "across") the old hardwood flooring. I have a
handyman-type person who will be doing the actual work, and he said he has
done hardwood flooring before. But, I am the one who will be deciding how
it will be done. He'll be renting the special nailing gun, etc.

I have to decide how it will be finished. Due to the apartment renovation,
the old hardwood floor had a number of sections that needed to be filled in.
I had the guy first install the same type of #2 red oak 3/4-inch unfinished
hardwood to do the fill-ins, thinking that I would probably then just
refinish the old floor. We even rented a sander and started sanding the old
and some of the newly-patched flooring. But, I later decided not to
continue with that and I am going to install the new floor on top of the old
one instead. Nevertheless, I now have some small sections of nailed down #2
red oak 3/4-inch unfinished hardwood on which I can test out different
finishes since it will be covered up by the new floor.

I've tested a couple of colors of polyurethane with stain in it, and I don't
like how it comes out -- they are all too dark. Plus, I am thinking that if
I can just use clear polyurethane without any stain coloring in it, if the
floor later gets scratched and damaged, it would be easier to just sand the
scratches and re-coat without having to match any stain color later on.

Here's the part that seems strange to me. When I test the clear
polyurethane on the unfinished hardwood patched areas that were just put
down, and that not sanded, it looks pretty good. The wood grain shows up
well and the color is pretty much what I want. But, when I put the clear
poly on the new unfinished hardwood patched areas that were already sanded,
it comes out looking bad (to me) -- it's much darker and the wood grain
doesn't show up well. I have a feeling that the sanding makes the hardwood
just absorb the poly more evenly, and not more in one part of the grain and
less in other parts, so it doesn't look very good.

My dilemma is that once the new floor goes down, I assume that I need to
sand it first to make it even before applying the clear poly. But, I think
that will make the coloration look worse than it would if I just applied the
clear poly first without sanding it.

Also, I've been reading some stuff online that says that the new hardwood
should be sealed on all sides. I've never heard of that before and never
saw anyone do it. Is that something that people actually do? -- seal the
new unfinished hardwood on all sides before putting it down? I doubt it,
but I have to ask.

Overall, any tips, suggestions, etc. anyone has before I start the
installation would be appreciated.

Thanks.