You can use something like Revulot to create disposable credit cards, or restricted credit cards that you can enable/disable with the tap of a button in the app.

I got one (including the physical card in case its required) on the Standard (aka free) plan for use when travelling or buying dodgy shit off the internet. For e.g. I used it to buy a phone plan in NZ, and only activated it for the one transaction. That way if Rocket Mobile had decided to sting me another month after I cancel it wouldnt have worked. They didnt scam me cause NZ people are good people (unlike US people... ) but still.

I just put $250 on there and will just burn through that eventually. If people try to scam me, at least my losses are limited to $250.

PS - if you get a Revulot account, use my promo code. I think I get money. Possibly you do too, but more importantly I do.