What is The Overall PROCESS and Experience of Invisalign? Financially as well?

I am an 18 year old college student on a tight budget yet have been wanting to close my minor gaps for many years. I went to a dentist who offered to do OrthoClear for $4000 but OrthroClear was recently bought out during a lawsuit with invisalign, no longer and option. I travelled to many other dentists and the lowest offer I got was $8000 for invisalign; too high for my small budget. Luckly i contacted the dentist that offered my $4000 for the orthoclear and can perform invisalign for my minor corrections for $4,500. I will still call other offices to see if they can beat that price though this dentist is a good one so i'll most likely stick with him. Can someone fill me in on the overall process I will have to undergo from the moment I step into the dentists office? Payment plans? (I dont have dental insurance) and such? Will it truly be $4500 or much more if there needs to be other exams and charges? I just dont wanna end up paying more. Thanks! Also the invisalign treatment.
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Check this out: http://www.invisalign.com/generalapp/us/ After you have your impressions taken, they are scanned into a computer. A virtual model of your teeth is created in the computer. Very small movements are done on this virtual model. From this computer image, a real model of your teeth is made. Some more very small movements are made on the virtual model, and so on. This keeps up until a whole series of thin plastic appliances is created to guide your teeth to the desired end position. The plastic is thin, but pretty strong. When it first goes in, it feels tight, because it is pressing on the places on your teeth where they have to move. After a few days, the tighness goes away and you know your teeth have moved. You change appliances every two weeks until your case is done. In my rural Mid-Atlantic general practice, I charge $3,000 for most Invisalign cases, which is less than traditional braces in most cases. I have heard that some charge more for Invisalign than they do for braces, though. The thing is, I am not a specialist and I choose to do only "easy" cases that will not require extra devices to be used in conjunction with Invisalign. This can add to the fee significantly.
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