Cowboy Bob
Horse Player/Guitar Wrangler
I'm not sure if Audacity even lets you export to a .wav file (?). And don't .wav files take a lot more space than MP3 files (thinking of Dropbox space) (?)
Yes it will and yes they do.
Let me expand on this: Although I don't use Audacity myself and I had to look it up here  Converting Audacity to Wav files I was certain that I had gotten wav files from clients that do use Audacity.
Looking at the tutorial, the only things that I would suggest for a project such as I have described would be to save the wav file as 24 bit and 48kHz. You may not be able to play that with a standard wav player though, it depends on what you use. I think windows media player will still, but it is the best combination of bit depth and sample rate for quality vs file size.
YES the file size is greater for a wav file. For example an 5 minute MP3 file of about 12 MB or so is going to be 25.8 MB at 16 bit 44100 kHz, or "CD Quality", and at 24 bit 48000 kHz it will be 42.8 Mb.
However the quality of the audio is far superior AND a person would not need to leave that file on their dropbox once it was picked up, so that would save space. Free drop box offers....what 2GB which is really quite a bit of available space.
And Marv is correct. I do provide a dropbox link to clients to upload and they also to me, so no biggie either way.
Just something to think about, and perhaps some fun being able to get and share a higher fidelity recording of your hard work.