I have this gap between my front teeth and a slight overbite too, I guess. Treatment options? (photo)

You're not too old to straighten your teeth.  Teeth move in adults just like they do in children and teenagers, but sometimes can be a little more stubborn.  It's hard to tell from your photos if you are an Invisalign candidate, as I can not see your bite.  It certainly looks like...

You can never reduce a 10mm overjet with 10mm enamel spacings, which would mean 0.5mm gaps between 20 upper teeth!!!!!!!!!!!!!!!!MY opinion is little or no spacings, but having 2 upper teeth extracted.Your lower teeth may also need realigning as well.I would definitely ask your dentist for an...

Invisalign fee structure is based on the type of case that is needed.  There are several levels of fees. 

The average (and Invisalign taught way) is 2 weeks for each Invisalign aligner tray.  Some offices have rushed it and done one week each, but the cases relapsed very quickly.  Three weeks is the most I would do, but even then that is a bit long.

The folks at Align have a lot of experience, so their advice is likely accurate. You may submit an alternative to see if they think it would work. I would consider regular braces instead. Much more predictable and faster. 

I think invisalign would be a good option. However, looking at your photo you may have a slight openbite. Normally upper teeth need to go over your lower teeth. The photo can be deceiving so I would recommend you go and see a local orthodontist to make sure your bite is proper. I think you teeth...