Looking for able developer or small agency for a client we've outgrown

We have a client that we've outgrown, and we're trying to find someone else who can take them on. The client and the site were inherited from another vendor in the Twin Cities, and we were able to bring the site to a stable, working version. This client has been with us since January of 2014.

The site has 150 users and is used as an internal document store and communications tool. There is no anonymous traffic, all traffic is logged in. There is a heavy reliance on Solr, with search being key to the site. It also interfaces with a mailing list that makes the content on the list available on the site as well, and searchable. When new features are asked for by the client, we really are not able to know if the changes we are hoping to make will negatively affect other parts of the site. This is one of the challenges we have.

We'd like the client to find a freelance developer or small agency who can give them the attention they deserve; someone who has a great attention to detail; is strong in PHP and backend developement; strong in the Drupal 7 API; strong in their knowledge of Solr; has good soft skills; has good project management skills. This is not a brochure site, there will be little (if any at all) cosmetic front end work. This site is all about the integration with Solr.

We'd be available in the transition to the new person or company to answer as many questions as possible. I'm not sure if this should maybe have been posted as a job or not, but I thought I would start a discussion and see where it goes.

If this sounds interesting, or you know someone who might be interested, please contact me directly for more information. Thanks.