micro chip

 First, I would ask which brand is it they are using.  Home Again is the most common.  It does require annual fees.  The scanners always can tell if there is a microchip present, even if it is another brand.  I don't know if they can read the numbers.

 With Home Again, let's say you lose your dog.  You phone them, and they send out fax (or email by now, probably) notices to all vets, spcas and shelters in a radius of (15 miles?  not sure of the area) of where you lost the dog.  So all those places are on the look out if someone tries to bring the dog in and claim it is theirs.  Or maybe someone brings the dog in as a found stray (like the local pound), then they can check the notices to see if your dog is up there.  This part of the service is not available if you do not register each year.    You can call Home Again or look on their website for additional info.

 I've had mine all chipped at SPCA events for like $10 - $20.  if you have someone who is relatively calm, experienced doing it -- rarely do you even hear a dog yelp at all.  NONE of mine have (two different times).  I've NEVER paid an annual fee.  The chip is about as big as a grain of rice -- as       she said any scanner can detect the chip, but may or may not be able to 'read' it.  I'd call around -- see if your local shelter ever does it at fund-raisers or what they'd suggest. 

That's pretty expensive.  You should be able to get it done much cheaper.  Lots of shelters and animal controls offer low cost clinics several times a year.  You don't have to register Home Alone every year or any of the other brands.  The registration is for "extras" and not worth the cost, IMO.  A scanner will work on the chip.   The initial registration, in your name and with the dog's info, is included in the cost of the chip. 

Freedom

It does require annual fees.  The scanners always can tell if there is a microchip present, even if it is another brand.  I don't know if they can read the numbers.

Home Again does not require annual fees.  They're optional once you've paid the initial cost.  I have two of my dogs chipped with this brand and I get the emails telling me I "need" to pay and register them.  It's just a ploy to get you to pay extra for some extra services they provide. 

Almost every vet and shelter has universal scanners that can read all the brands of chips.  Yes, they can read the numbers too.  It would be cost prohibitive to expect vets, shelters and animal control facilities to have a different scanner for every brand of chip. 

ETA: this is from Home Again's site:

If pet owners decide not to renew their annual membership, will their pets’ microchip ID codes and information still remain in the HomeAgain database?

Once entered in the HomeAgain database, microchips are registered for life, whether or not pet owners renew their annual memberships, and contact information may be updated online anytime free of charge by logging into HomeAgain.com. However, if a non-member’s pet is lost, they are not eligible for the value-added benefits included with the annual HomeAgain membership, such as proactive outreach to local PetRescuer volunteers, medical insurance for lost pets, travel assistance for found pets, the 24/7 medical hotline, etc.

 I would look for a local event that offers micro-chipping - here its usually $5-10 at those.

Our local humane society includes the microchipping in the adoption fee when you adopt a pet from there.  But, I think they sometimes offer the service to the general public for a much lower price than what you mentioned.  You might call a local shelter near you, or perhaps the county/city animal control department (whoever handles dog licenses) to see what they can suggest.

We get those annual reminders, too, and at first I thought I had to pay the annual fee for the microchip info to remain available in a database.  But I found the fine print similar to what Jackie posted and decided to ignore the emails.  The important thing is to update things if you move or change your number.  I've found stray pets who have out-dated (or no) information on their chips when I bring them to the shelter for scanning.

I've never had my dogs sedated for microchipping, and $70 is a whole lot more than I've ever heard it costing. Like Callie said, it's like a grain of rice, it's inserted, and my info was added to the chip account. I've never paid an annual fee or anything like that. (I can't remember which brand my vet uses, but I can look it up if you'd like. Both Frisby and Mozey got their chips at the shelters right before I adopted them, and it was part of the adoption process.) I'd look around at shelters and events, as others have recommended.

SadieLady

I know there is debate over this, but this vet said they only do it under sedation. I wonder if that's true of dogs that aren't undergoing any surgery

I've never heard any debate over it and I never heard of a vet saying they only microchip under sedation.   I've never had a dog sedated just for a microchip and I've seen lots and lots of dogs chipped without sedation.  It's a very minor procedure.  Maybe you should ask that vet's office for clarification.  If they confirm what they told you, I'd get her chipped elsewhere for much less.

 I've had several dogs done without sedation. Luke was done under sedation because I had it done with his chip. Callie was not sedated, and she is the second one I've had done while I hugged the dog and kept it from noticing. I think Luke's I paid $50 for, and I think Callie's I paid $25-30 for it.

 Tara -- that vet certainly maximizes his income opportunity!  It is truly NOT a big deal.  And $70 is absolute robbery.  I honestly didn't even know you *could* pay for anything annually.  It's kinda silly -- the chip does what the chip does.  It's there -- they read it. 

The *only* dog I've ever seen pitch a fit -- given the owner's death grip and screaming at the tech?  I'd have cried too -- if I had to go home with them, that is!  

Seriously -- that vet is making a mountain out of a molehill.