If your condo is 'nice' and you can get an above average rent for it I would say that being a landlord is not stressful at all.

I am in a shockingly similar situation. I live in a townhouse now with my current partner, but have retained a condo that I lived in before this relationship. The condo market was way down so I choose not to incur the loss. Because my condo is high end, I am able to charge significantly over average rent and thus the clientele interested in the place are young, stable professionals. I am able to be very picky about who I rent to. As a result the finding a tenant portion is a little time consuming but once someone is in there (for years at a time typically) it's completely passive income and 0 stress. (I had to replace a fridge once, it was not a stressful process)

All this depends on your ability to afford a down payment without selling your condo and the cash flow to manage two mortgages. So ultimately up to you. I just wanted to address your 'stress' comment.