roof access - door or skylight?

When the roofers come to reslate my roof
I want them to put in a door so i can get up there
and clear out leaves without dangerous ladders...

Is there an openable skylight on sale somewhere
or is it better to have a skylight to let in the light
and a separate roof door to get through?

What types are recommended?

I will be insulating above the ceiling (not under the tiles)
so skylights and doors dont have to be insulated..

--

[george]

~