I’d say it’s more hassle than it’s worth. It’s enough doing mobile when you drive with all the equipment you carry getting it in & out of the car.
With public transport I can’t imagine you’ll be able to fit enough clients in per day to make enough money for it to be worth while. And it isn’t just jumping on a bus, you’ll have to walk to & from the bus stop with all your equipment. And not everyone lives close distance to a bus/tram stop. My nearest one is a mile away. That’s a lot of walking when you are carrying all that stuff.
Plus timings between clients & making sure you are on time.
I Don’t want to put a downer on it, but just trying to be realistic. x