However, the guy said he was owed money from PayPal (a large check that was on hold) so he didn't want to use PayPal.

PayPal owns Venmo.

He convinced me that I could just file a chargeback with my credit or debit card on Venmo or Cash App...

https://help.venmo.com/hc/en-us/articles/235171088-Cancel-Payment

"It is not possible to cancel a payment to an existing Venmo account."

Your credit card company will not honor the chargeback, because Venmo will provide evidence that the charge was authorized. Googling "venmo chargebacks", "cash app chargebacks", etc. will find many, many people hit by this sort of thing.

This is a scam.

Absolutely, positively, without any doubt, this is a scam. You cannot get a refund for Venmo purchases. For real: Venmo is ONLY (absolutely only) useful for sending money to people you know. You cannot use it for general "buying stuff", because there is no buyer protection.

This is 200% a scam

The smoking gun is the same detail as in my answer to this question - the unnecessary convincer.

I'm going to cut and paste from that answer, and I think you'll see the relevance.

"The corporate site shows other people use friendly persons login and have also bought desktop computers using his discount."

That one point, to me, is the smoking gun and huge red flag. Its a very high risk of being a scam.

Why the red flags at that?

Scammers are confidence tricksters. Some themes are totally pervasive - some kind of "too good to be true". Some kind of "convincer". A friendly helpful person who seems to like and trust you and says they are glad to cut a corner to help.

Now, the thing about a convincer is, most genuine situations people don't actually throw them in. The excessive step to show you it's safe, is WAYYYYY further than the steps needed to tingle my red scammer warning lights.

Think about it. If your (real-world) friend offered to pay the £200 flight cost for a holiday this time round, and you pay back your share, that's fine. But if he opens his banking app and puts it in your hands, gives you the login, just to specifically prove others have gone that way on holiday costs with him, ..... Isn't that just a little bit weird?

That's what I mean by being an excessive step too far. A genuine person just wouldn't do that. They'd say, "I work there, I've checked my employee discount, its $X to me...." and then discuss making a payment in some nice safe way that you get your cash back if the thing doesn't turn up.

Coming back to your situation....

In your situation, someone wants payment via an unusual system (Venmo). We know for sure, 3 things about him:

1. He wants paying with an unusual, irreversible, payment method.
2. He lies when asked if its an irreversible payment method.
3. When you persisted in doubting, he sent you "screenshots and accounts of people who have supposedly bought from him".

That's the twist, and the lie covering it, both then followed by a wholly unnecessary convincer. That convincer? That's the one that says its 200% a scam.

Exactly like the example of the other answer above. Unlike a "normal" vendor, here we have a dodgy as hell sales pitch, where the fallback is then "look at these sales other people were happy buying with" AKA dodgy screenshot.....

That's classic scam stuff - seems quite common in online scams these days. And it proves nothing, because you don't know if its real or not, and because you want certainty for you not just claims by the vendor (scammer) that loads of other people purportedly trusted him.....

If he wanted to convince you its safe, he could make it safe. But he doesn't. It takes very little effort to do so, but he isn't interested. But despite that, he is interested enough in selling to you, to create (it seems) an excessive convincer.

"I won't make it safe, but I want paying by a weird/uncommon irreversible method, I've lied to you about the safety when you had a concern, and when your concern persisted I still didn't make it safe, instead I showed you the screenshot. And just look at all this evidence it's really okay! All these other probably- nonexistent names and amounts, who the dodgy- and- probably- fabricated screenshot says have been trusting! Surely now you can agree it's safe!"

It's a scam in the end. At best it's such high risk of being a scam in the end, best treat it like one, anyway.

As of today, Venmo is not intended to facilitate marketplace transactions, so as other answers have noted, proceeding with this is ill-advised. However, do note that this is on the roadmap for the future.

Straight from the horse's mouth:

Can I use Venmo to buy or sell merchandise, goods, or services?

Venmo will soon give buyers the option to identify a payment as being for a good or service. This means that it'll automatically be covered by Venmo's Purchase Protection Program and the seller will be charged a small fee of 1.9%+$0.10 of the transaction. These fees will only be charged to personal profile recipients when the buyer identifies the payment as being for a good or service. Payments to your friends on Venmo that are not identified by the sender as payments for goods or services will not incur a seller transaction fee.

Can I currently use Venmo to buy or sell merchandise, goods, or services?

Venmo was originally designed for people who know and trust each other to send each other payments. However, we’re in the process of growing our services to accommodate the varying needs of our customers. The only way to accept payments for goods and services on Venmo is to apply and be explicitly authorized to accept Venmo for purchases.

As a customer or “buyer”, you may use Venmo to pay for goods or services in the app by paying an authorized business profile, by using a Venmo Debit Card at merchants that accept the card, through mobile websites or apps that are approved to offer Venmo as a payment option, or by using your in-store QR code at select merchants.

For more information about accepting payments for your business in the Venmo app, see this article.

Venmo may NOT otherwise be used to receive business, commercial or merchant transactions, meaning you CANNOT use Venmo to accept payment from (or send payment to) another user for a good or service, unless explicitly authorized by Venmo.

Unless directly given the option by Venmo, DO NOT USE VENMO TO TRANSACT WITH PEOPLE YOU DON’T PERSONALLY KNOW, ESPECIALLY IF THE TRANSACTION INVOLVES THE PURCHASE OR SALE OF A GOOD OR SERVICE (for example, concert tickets, electronic equipment, sneakers, a watch, or other merchandise). These transactions are potentially high risk, are not allowed under Venmo’s User Agreement, and Venmo does not have a protection program for such transactions unless directly offered. So:

If you send a Venmo payment to an unauthorized business profile or another individual for a good or service, you could lose your money without ever getting what you paid for. If you accept a Venmo payment from someone for a good or service via your personal profile (instead of a business profile) and we later review the payment, we may reverse the payment, meaning you could lose both the payment and the item sold. This review process may not occur until after you attempt to transfer the funds out of Venmo.

Thank you for your cooperation!