Unless I've missed something, if you're going it alone or just with you and a partner, why not self name?
Raging Squirrel Shop Fitting
Squirrel Shop Fitting
Squirrel and Partner Fitting
Raging Squirrel
Squirrel
It's simple, and surprisingly powerful in that line of work. As what you are selling is essentially yourself and the quality of your own work (rather than a product), the instant and real name association is your biggest currency to getting you yourself recognised.
If you want to go down the line of a "proper" business name, do your research. Google, Companies House. As daft as it sounds, you want to know silly stuff like is your name already in use by someone somewhere close by, is the domain name available to easily allow me to establish an online presence for marketing, has the name existed previously - especially locally - and did it garner a bad reputation? It'd be harsh to pick a name, throw yourself into the venture, and then find that you have to change your name because someone two towns over is doing the same work under a similar trading name, or worse, you are being associated with a previous entity which failed and has a bad reputation.