how does an existing company roll in new revenue models into existing ones?

I've got a consulting business built around my personal skills and offerings. I've picked up a few sales people to help increase work volume (currently part-time outside of a day-job). The company isn't getting the traction it needs to tip, and my team is starting to loose focus and motivation.

I've started thinking about bringing in auxillary revenue streams to change pace. One idea that I've had is to take on some resale work (i.e. reselling software or non-competitive services) along with our own offering.

I'm not sure how to wrap this in, or where to start. Saying it out loud sounds pretty trivial, but when I think about the selection process, training, and other related tasks it quickly starts to feel daunting.

Any ideas how I can get a minimally-distruptive revenue boost that will reinvigorate my team and hopefully generate enough revenue to tip over into a sustainable, growing business?

So your sales team is not having success selling you. I assume you have some expertise in some niche area and they are finding business prospects who need that expertise you can provide?

Your ultimate goal is to increase the business revenue. Instead of having your sales team selling other products, why not find products or other companies in that same niche/industry that can sell you?

Instead of using part-time, commission only salesmen who don't seem to be crushing it everyday - you should find established business partners in your industry and create relationships where they can make money referring their clients to you. Find people who are already successful in that niche/industry and convince them that their clients need you.

Reselling other products might be an additional revenue stream, however, if you don't have clients to resell to, you won't any money. Focus instead on understanding and solving the main problem.

If I were in your shoes, I'd start with the basics:

You say that they are currently working part time, outside of their day jobs - are you sure you're getting the necessary commitment from them?

If your team needs reinvigoration - are they the right team? If they are the right team, why aren't they invigorated?

If that's solved, I would start considering: does the team understand the services offered? Do they understand how to identify suitable potential clients? Do they understand how to sell to those types of clients? etc.

It's hard to give sales optimization advice without knowing the sales funnel. You might not be selling to the right people, or you might not be using the right pitch, or your sales team can't close, or it might be something else completely different (say, your company name & image).

As for additional sources of revenue, it's not uncommon for consultants to resell 3rd-party products that are complementary to their services. The trick is to stay focused on your consulting services and not becoming a sales consultant for others. This is accomplished by selecting a limited number of products that work exceptionally well with both your solutions and your customers. This way you'll be offering "full packages" that may boost your value in the eyes of potential customers.