One thing I should probably point out about techs and attitudes (and this actually goes for engineers as well as a very large percentage of jobs within the hi-tech industry and the people employed in them) is that most of them don't get into it because they're necessarily "social butterflies" or even extroverts. They also sometimes have a difficult time in trying to relate to non-"geeks" or even just talk to them without it getting into an area that's going to involve tech or getting too technical. It's usually not a deliberate thing on their part either--some of the most brilliant techs, engineers, developers, Sys admins, etc. I've ever had the privilege of knowing or working with also sometimes not been among the most social-able of people when it comes to dealing with non-geeks. That doesn't make them 'bad" at their jobs, however. I've come to find over the years as I've attended various events within the industry just how many of them have trouble in trying to talk to people not in the industry or really socialize with them outside of subjects that tend to be traditionally associated with geeks.
Yet, when the subjects of sci-fi, different software or hardware platforms, configurations or projects, troubleshooting, hacking (not in the negative misuse of the term most people have mistakenly come to think of--actual hacking as in figuring out how to do something in an unconventional way (ie things that may not make much sense for those not into it such as building homemade radios and transmitters or turning the back of one's truck or SUV into a giant receiver for a homemade broadcasting station or installing a different operating system onto say a microwave or a console that it was never designed to run or building a computer within a coffee pot, etc.--and believe it or not, some people actually have done these things because they just wanted to or for the sake of it), or certain games are brought up and it's something you may know about or else are familiar enough with or come across in a way that you seem to understand or are familiar with the subject, some of them will talk your ear off about that subject or even appreciate it.
In other words, it takes some understanding--as it can with anyone else--of them and respecting the fact that they sometimes just prefer being around electronics or computers, etc. than they do people or else want to be around people, but have difficulties in socializing with non-geeks and some are either just introverts or else may have grown up feeling like it was somehow a "bad" thing/a stigma or ostracized/rejected for being a "geek" and having the interests they have and/or therefore just have difficulty at times in relating to others or else in just being understood.
Again, that doesn't necessarily make them "bad" techs, engineers, sys/network/database admins, etc. nor will their work be subpar. One thing has absolutely nothing to do with the other.
On that note, I will admit that some of them do have an attitude problem in trying to talk to people who may not know as much as they do (it's not something I happen to agree with either--in fact, I prefer the Linux and most of the open source communities' approach in helping and educating people instead). However, it's not always intentional and it's also something I've even been on the receiving end of things.
What I've come to find is two-fold in that part of this goes again toward the lack of understanding/communication issue in that it's very, very easy for someone who works in the industry (not just a tech) to converse with someone and get into all the technical talk (something I'm aware of being guilty of at times). Some of us (like me) are made to feel guilty or bad about it when we're told by others who may not know as much as we do and/or are not part of the industry or community when we get into such discussions or explanations that we've gone "well over their heads" or else are dealing with glazed over looks of boredom. In some cases, some of us don't mind or are willing to try and explain things in a way that may make more sense to someone who doesn't work in the industry or isn't involved within the community.
However, there are others out there (the ones who often get described as having an attitude) who do mind it and may roll their eyes, etc. because they feel frustrated about it and either have difficulty in trying to or else feel they can't describe something without getting further into technical matters. So, some of them may come off as making it out to be like it's not "their" job to try and educate others about things or else react out of that frustration and may say things they more than likely don't specifically intend to come across as they do.
The best advice I can give you in dealing with them is to think of trying to deal with someone who may speak a different language from you. They may be just as frustrated in trying to express things to you as you may be to them and some may speak the language you do "better" than others might or with varying degrees of accents involved.
That said, though, in terms of what to actually look for in a tech, definitely avoid the "certs" (ie certifications)--especially if their "qualifications" mainly consist of Microsoft certifications (not just A+, which is among the lowest out there). It's not a Microsoft issue, actually, as it is the process to obtain the certifications. Typically, people who obtain the certifications are only taught what's on the exam and that's it--they're not taught things as they may appear in a "real world" situation or environment nor to really think for themselves nor develop crucial critical/analytical skills to troubleshoot things. They're mainly taught that if a situation arises to look it up in their manual, as Steph had commented.
Most companies, incidentally, won't hire techs who only have certs for this reason and haven't for the past several years (it's not just because they feel it's more a piece of paper/lack of actual qualifications, but because it's not cost effective as well as frustrating to other staff who may be working with them if a tech with say an actual degree or their boss has to take the time to explain things to them or do their jobs because the person with the cert doesn't know what to do when a situation presents itself or it isn't in the magical manual/book of their's, etc.).
There was actually a letter published in a major Linux publication several years ago about this that was written by an executive working for one of the biggest/best-known companies within the industry and he made the comment that if any resumes came in from people whose main qualifications consisted of certifications, that they were immediately thrown into the trash/shredded and not even looked at/read, nevermind considered because of this. He, himself, actually used to teach certification classes and so knew all about them and what was/wasn't taught, etc.
There are, of course, exceptions to this (Cisco certifications as well as to some extent, Red Hat certification). However, they're not what I'd consider relevant to your current situation.
However, even if it's a small repair place, I'd be careful and look into things--not just beyond asking questions. There are some online sites which may have forums involving various businesses, complaints, etc. which may be worth investigating (although, take some of it with a grain of salt as it were as I'm sure you can imagine). Also, definitely ask them to go into how they look into/troubleshoot problems and diagnose them as well as what (if any) procedure or methodology they might use in doing so. In addition, ask them about the handling of components in terms of pricing (although, a number of places out there may have either the customer order the components or else may order it from places that are also available to consumers--regardless, shop around on prices on your own just to further make sure you don't get ripped off). Find out as well (and put into writing) whether or not they may offer any sort of "guarantee" for their work.
In addition, as they'll be handling the internal components most likely, ask to take a look at the actual workspace where your computer might be handled. This is very important so you can see the conditions as well as in whether or not they have not only the proper tools (especially that anyone who may be working there has and wears a wrist strap at all times while handling exposed systems or components), but also isn't keeping any exposed components anywhere they shouldn't be and any new hardware, ideally, still in its anti-static container or bag until it's actually required to install it, etc..
If I think of anything else, I'll be certain to add to this list.
Edited because I just now realized I inadvertently said the opposite of what I meant initially about people with certifications.
Instead of saying avoid them (as you should), I somehow accidentally may have said to go with them which was definitely not what I meant/intended.
