I would recommend Men's Health Boston http://www.menshealthboston.com in Chestnut Hill.
From my experience, they are solid. Since my insurance pays for visits, labs, and most scrips (but not HCG, sadly), it is affordable. I use their in-house lab and pay out of pocket for my HCG at a decent price through a compounding pharmacy.
There are other options in town -Boston Testosterone Partners (in Norwood), but I know little about them. From what I hear, it costs a few hundred to start up, and the standard trifecta (T+ hcg + AI) costs around $350 every 10 weeks.