They take your money and could even ask for some more for a FULL PACKAGE, only for 599.99 and only today.

So you didn't get WannaCry on your main PC and just curious whether or not any of those virus removal gigs are trustworthy, right? Well I can't say since I always backup my stuff and sailing the high seas leads me to good habits in virus prevention, thats my suggestion.

No different to an electrician, mechanic etc etc. We'll fix it and it will only cost an arm and a leg.

The key point is to not keep all your eggs in one basket. Backup, backup, then backup a few times more. Then if the worst happens flattens the hard drive, reinstall then you still have all your data. I agree, I wouldn’t want some third party rummaging around my data either.

I think it varies greatly from business to business. There would be some genuine businesses out there that pride themselves in completely rooting out infections restoring your data and might use some expensive data recovery software in the process as well, and, some are going to do slapdash basic virus scan jobs. Some will be reasonable with their pricing while others will totally overcharge you for their time. If you have a shop-front and are intent on keeping it in this day and age you don't do sham work, but you might do overpriced work. Some creep working out of his garage might be looking to steal your sh*t with your back turned ... you get the point. There is no right or wrong answer because it's incredibly varied.

As for whether they can do things that the "layman" cannot ... well, that also depends on the skill of the layman doesn't it?. Generally the skill level of users who call these guys for help is minimal - the kind of people who don't back up their stuff and have a contingency plan in place when all hell breaks loose (or people who live alone with no family & friends to give them advice). Some businesses even advertise with tongue-in-cheek jokes about the satisfaction their clients have with their work, even if the work was only something simple.

From those I know that have worked in computer retailers, generally they have a USB stick they boot off of that's configured with multiple programs. They just run a series of them depending on what the issue is. Most times it fixes it, otherwise they'll run a "recovery". As far as digging through your files, larger retailers tend to have a lot of customer computers, so they don't have time to do it.

However, I wouldn't trust any personal information in the hands of a stranger. There can always be that one bad apple who thinks it is a fun game, and it's not really difficult to hide a keylogger or some other malware on a PC, and return it to the customer infected. If the customer didn't have AV in the first place, good chance they probably still won't afterwards.

It's only something you'd need if you don't have an OS reinstallation disk or need to recover critical data.

This about sums it up.

Also, these days, there are few real "viruses" out there (anyone remember boot sector viruses?). The only thing that comes close is cryptomalware.

Actually yes, there is a huge difference: skilled tradesmen perform technical skills which they had to receive specific training for over a period of years, and which the customer can't do themselves because they don't have that training.

In contrast, shops like the OP is talking about are not performing a trade skill, don't require specialized training to do the task they are offering, and are not doing anything that the customer couldn't do themselves.

So whilst they are the same in terms of ripping off the customer with extortionary prices, they are different in terms of how actual tradesmen provide a necessary service, whereas the people described in the OP do not.

For anyone who is interested, below is one of Mark Russinovich videos that goes through using a couple of SysInternal tools. If you ever want a challenge of removing malware from a computer without an AV, give it a shot. There's more up to date videos floating around.

https://www.youtube.com/watch?v=YGtsMa9wbjw

I have no idea what the training is like in your country but everything and I mean everyone in Australia is trained in a job position for a certain amount of time, be it years or months or weeks or days which makes it virtually the same.

I'll agree that formal training isn't often a required thing for such places. Do keep in mind though that:
1. There is a difference between a certificate holder and a skilled individual
2. A formally trained individual is in no way guaranteed to be more skilled than someone self-taught. It is a baseline set of skills at the most.

You've lost me. So all customers who contact a computer repair business can do the job themselves? Isn't this the point of them contacting the business in the first place - that they need help? Who gives a toss whether you believe the skills required to recover from a virus is easy or not. The customers obviously don't have the support around them TO do it themselves. Suppose you don't have family and friends around them, only have one computer which is the only internet-capable device in the house, no backups, and you get locked out of your laptop / it crashes. Who's to help? Are you available for free 24/7 to fly over and help?

How is this not a necessary service? Again, if you need help, and no-one else can help you go to a business who can. No different to a trades-person or mechanic in that respect. Some people can't change brake fluid/coolant/engine oil in their cars and use a mechanic, but that's easy isn't it? No formal training is required to do that, yet people use these guys all the time. If my tap is leaking I can fix that, but the old lady down the street can't so she calls a plumber. No point in being snobbish about the skill level required for a job - if someone can't do something they seek help from someone who can.

Ancient-Red-Dragon: you sound a bit out of touch with the real world. What some people consider the easiest thing in the world can be like "rocket science" to others. And vice versa.