A porcelain veneer costs about $500-$1100 per tooth and they last approximately 10-15 years (so no not permanent). With a porcelain veneer there is a 2-step process that is completed over about 6 weeks. In the first visit, the dentist will shave and shape your tooth/teeth (so in answer to your question about damaging your teeth - they will be altered in the process). Lumineers cost about $700-$1300 per tooth (a lumineer is not permanent either and will last about 10-15 years also). A lumineer can be placed without drilling, so it can be a reversible procedure - causing no damage/alteration to your teeth. Most dentists charge per tooth (regardless of how many you need done). I will list the site that I found the price information on. On this same site, they also say that most dental insurance does not cover these procedures because they are cosmetic.
If you are interested in veneers/lumineers and your insurance won't cover them, you could look into a discount dental plan, as many discount plans discount cosmetic procedures. I have located a website that you can compare discount dental plans, as I only have experience with Ameriplan. I will list these sites as sources below also for your reference.
I hope that this information is helpful.
http://www.costhelper.com/cost/health/veneer-lumineer.html - Cost of Veneer/Lumineer
http://www.apdiscount.info - Ameriplan Discount Dental
http://www.DentalPlans.com - Compare Discount Dental