I did something similar last winter to get more people into the stone thing. For every client who came in for a 90 m. massage, they could have the use of warm stones included in their session. Except, I would just use the stones heat up each body part before massaging and maybe again after working the area. I used a double stone introduction to the back. In areas of inflammation or that were bothering the client, I would also combine the marble (I am trained in LaStone therapy) It was so popular that this winter I am going to add it to my menu as an add on service.
Many clients wanted to try a full LaStone session after that whereas some others still wanted the massage part but were willing to pay extra to add some of the stones in to the session.
Another combo is to offer free foot/hand work with the stones.
Something to think about: when combining hands-on massage with hot stones, be careful not to do too much of both or the client may end up feeling tired and sore for a couple days. In LaStone we are taught not to combine massage with a full stone body sequence, the reason given was that massage brings heat to the tissues as well as the hot stones and that could lead to too much inflammation in the body.
I'm not really sure if that's the real science behind that reasoning but here's my anecdotal evidence: a friend of mine wanted hands on massage in her LaStone session (which I wouldn't do for clients but she is a close friend), so I gave it during her session and she felt like sore for a couple days after. I have also had clients who have recieved my work mention afterward they were nervous to try it at first because post-soreness had happened to them when getting regular hot stone massage from other therapists as opposed to a LaStone and the other therapists had used the hot stones in with the massage more often than I did.