I'm glad you mostly? liked our service. Here's a better (long overdue) explanation: our billing system attempted to bill you because you had a negative credit balance (owed us) - most likely from forgetting to destroy an instance. However there's a threshold for any credit card charge around $5. I suspect that we later experimented with a different threshold criteria, which then caused the billing system to attempt to charge your card the balance owed - a long while after it was accrued.

We do now have better billing history reports so you can see what caused a charge, although sadly the customer service still isn't much better. Source: I am the CEO/founder and still handle most customer service.

Your service helped me immensely when I was getting started with machine learning, but had no budget and just a laptop. For me, everything “just worked”, and I learned a ton about Docker and created my own system to handle the ephemeral nature of the computing systems by automatically backing up training checkpoints, programmatically finding the next best “deal”/“bid” and resuming the training on a different instance.

Was very very cool, and I generally recommend it to anyone I come across who has modest needs (<25 GPUs).

I did find the throughout was not always accurate at the time. This was about 2 years ago. It was fairly frequent that a listing would say “300” to “1000” Mbps Up+Down, but would actually get an order of magnitude less to any of the big cloud services (GCP, AWS, etc). It wasn’t important to me that the speed was low, but it was important that it didn’t match what was “advertised”. For certain workloads I would have gladly paid more for higher throughput but that’s not really an option when the listings couldn’t be fully trusted.

I also heard there may be some opportunities to market your technology/platform for “on-prem”, “on-demand” GPU clouds for large enterprises so that a pool of corporate GPUs could be efficiently used and accurately billed to a variety of internal stakeholders. Could improve asset utilization for capital intensive on premise GPU’s.

Wow, I was definitely considering trying this out until I saw your comment. They charged you mistakenly, didn't detect it on their side, and then never gave you a reasonable explanation for why? For me, that's a definite no-go.

That's such a small thing tho. It was a tiny amount and presumably they would've refunded it had it gone through. It's also possible they would've discovered it themselves soon enough, since many companies only look at the money books at the end of the month.

Also, I doubt you'd get a "reasonable explanation" from any other company - at best they'll say "sorry it was a (human|software) error, we've taken steps to ensure it won't happen again", as disclosing anything more is usually against company policy.

Scammers use small changes on stolen cards as a test. If the test change doesn't get noticed or flagged, later a much larger is sent through.

"That's weird" is a not an acceptable answer for a card was charged for any amount.

Yeah, that was my first thought too, but the card was already expired, and a scammer would probably have known that immediately without testing (since they presumably need the expiry date as well as the card number to charge anything).

I've had mini-charges like these from other cloud providers, too, but then I could confirm the reason for it (some sort of storage I'd missed while deleting the instances).

the amount doesnt matter, it's about getting charged for no reason. You never know how much it would be for the next person they charge

It matters when evaluating their response. If they said "huh, weird" for a 200$ charge I'd be suspicious, but for such a small amount, I totally see why they wouldn't bother explaining how it happened.

you can't keep customers like that

I’ve used vast.ai many times over several years. I use the “top up” approach. Never any unsanctioned payments.

Key context here is vintermann had a balance due (and gave no indication that he disputes that). Of course there should have been a better explanation - especially if asked for. But to the extent there was a mistake, arguably it was simply in not charging the card earlier.