No special access issues
The crag is located near the crossroads of Kehä 3 (103) and Uusi Porvoontie (170).
Puuhamaa climbing wall is located bottom of pass between couple of small hillocks. There are how ever couple of residential houses nearby so obviously I would be cautious of unnecessary loud noise making. Access to Puuhamaa climbing face even from furthest parking lot takes only about 5 minutes and from closest takes only like 30 seconds. There is a obvious clear pathway to the climbing face which is easily accessible with child carriage as well.
There are couple of bus stops(Vilkkula 2, H5005 and H5006) near by Puuhamaa crag. Getting there with public transportation should be pretty easy and straightforward as well. You can access the bus time table from here: https://www.hsl.fi/en