Coming down from maine, never been to boston. Thinking of making one day/night drives to boston to see what the hobby scene has to offer there. Any hotel recommendations for outcall? I probably won't have time to explore boston or do anything else, so what's a good hotel to make my home base for hobby outcall?

price isn't too much of a factor but I'd like to keep it under $400 ish a night

downtown? Cambridge? somewhere else? I don't even know all the areas

Parking and traffic is always an issue with Boston..  I think you will find you have a great choice of hotels that are easy access for visiting friends in Waltham.  It is right on 95 and there is a cluster of hotels right off the exit with free parking .

Have Fun!

Hi for safty a specific hotel would not be good but an area would be ok.
You already provided on great area make sure you can see the Charlies River from that area.
Another great place is Backbay.
Have fun

...you may want to set up camp somewhere else.

I don't think it's good to be even THIS specific on a public forum....