I did a 60km each way commute this past summer but I did find it draining by the end. I used a good road (race) bike. If don't want to buy from a shop and you have any mechanical know how and patience, it might be good to try and build your own. You can get a lot of good parts off of ebay and sites like chainlove.com and probikekit.com. It takes a lot of research but it can pay off both by having a cheaper bike and knowing your bike a lot better. For getting stuff to work, I mainly left it there, I left a few shirts and pants and brought the smaller things in my saddle bag or sometimes my spare empty water bottle.

You'll also have to budget for other things such as a few pairs of good bike shorts, jerseys (you can use other athletic shirts but they make sense for having a mid ride snack), bike shoes, helmet, lights...

It took me exactly two hours to make the trip each way and I had done a lot of road riding before, so you're probably looking at 5 hours+ each day and you won't feel like doing much else but sleeping when you get home. I'd recommend that you start riding right away, doing any other activity won't prepare you're muscles or your mind the same way riding will.