I use a cheap no-name $70 power supply (which is now < $60) and haven't had any issues. If you don't have any extreme needs I don't see why the budget ones would be a problem.

I just made sure to use fakespot and read some reviews before settling on one.

Amazon has a 90 day return policy which helps reduce the risk. I'd be more hesitant to buy one on ebay.

I was thinking about something like this. I'm just wanting it for testing items before posting on ebay. I wouldn't give a customer an adjustable one. I would just need to look for a supply like this one for example?

this is the DC power supply I use. Still hasn't burned out after being on for 5 days straight.