Invisalign costs are based on length and difficulty of your case.
Judging by the picture it shouldnt take more than 5-8 months to fix those gaps. It might even qualify as being an express case which is 5 months or less..(10) aligners total. The fees will range from $3000-$4500 and may be covered in part by insurance.
INVISALIGN WORKS FOR SPACE CLOSURE
Invisalign is a good choice for orthodontic re-treatment of the type that you require. However, it appears that closure of the upper space will also require some lower movement. Trying to limit treatment to only the upper will probably yield a less than satisfactory outcome - and maybe make it more likely that space opening will re-occur.
In your photograph it appears there is significant wear of your upper right canine tooth. It is possible you are doing some clenching and/or grinding of your teeth during sleeping hours, That may have contributed to the space opeing. I suggest you discuss with your orthodontist the possibility of using an upper nightguard as a retainer to give you some protection against tooth wear and simultaneously keep the spaces closed.
Invisalign to close spaces some years after braces
Invisalign sounds like a great choice for your problem. Since the photos do not show the details of your bite it is difficult to determine how long Invisalign would take to solve the problem. However, you may find that doing treatment on both the top and the bottom could SPEED UP TREATMENT and give a better result. This is because the spces may have appeared as a result of your bite, and having control of both upper and lower arches might allow a better bite to be created. The result might then be that the spaces don't tend to open again in the future. As far as cost goes, it varies from region to region and case to case. Expect to pay between $4000 and $6000 for this treatment.
How long and how much for retreatment with Invisalign
As always, the time and cost depends on the difficulty of treatment. Because Invisalign does not give a discount for single arch treatment you can expect the cost to range from around $4500 to $6500 as the size of the spaces you describe are probably to large to close with the less costly Invisalign Express treatment. My guess for time would be 6-12 months.
There is no price difference whether you need one arch or two arches treatment.
The price ranges between $4700-5000.
The duration of the treatment is about 6months to a year not including the retainer.
Invisalign Sounds good for you But lets look at your Bite
Invisalign is a great treatment for correcting relapse from braces. From the limited photo you have shown the space is working in your favor. Your front 4 teeth are crowded leading to them being crooked. They have moved forward causing you to have space. Once the teeth are re-aligned the space will close. Look into invisaling it can straighten and whiten your teeth all at once.
Treatment time 6-9 months
P.S. Make sure you are involved in the treatment and have a look at your "Clincheck" with your doctor prior to approving treatment. Not all Invisalign Doctors are the same so dont let price guide you, because your case can become complicated if not treated by the right doctor.
Invisalign is great for relapse cases
Since the majority of the work was likely completed with the first "go round" with braces, Invisalign will normally act as a refinement, and if the case can be done with 10 aligners or less then it will qualify for Invisalign Express®.
Fees will vary from state to state and city to city, so expect to pay around $5000-7000 for a full case, and $2500-4000 for Express.
Each aligner is for 2 weeks, so a 10 aligner case will be around 5 months. The average Invisalign case is 11-16 months, some going much longer.