This is a difficult one.
We own a small house that we rent out, which is ironic as our daughter has to rent, but selling wouldn't solve this as we couldn't recoup enough of our investment to help her since the financial crash and it does give us an income.
We have experienced the ups and downs of being landlords. Good tenants and bad ones. For the past few years we have had the same tenants, who are lovely and we have a good relationship. But before that, well put it like this, on one occasion we didn't return their deposit! We manage the property ourselves, but use a rental agency to do all the checks for us when tenants leave. To be honest, I wouldn't want to manage it on my own, despite having such lovely tenants, but that's partly because it's not nearby.
You can use management agencies to manage it, but they charge a lot and the ones my DD has had to deal with do very little. She has to fight to get anything sorted out, including health and safety issues when they have a young child. Our tenants can ring us up and we sort things out as quickly as possible. The best way through if you decide to manage a property is to build a network of trade people to call on when necessary. I would think that might be easier for you as your Mums house is nearby. It's definitely more of a hassle managing a property from a distance.