Hi
It is great that you have a business idea. The question you asked is very real to any business especially when it's a startup. You really don't want to put something out there when there is no niche for it or when it is moving slowly. so here is what I would suggest.
a) Do a thorough feasibility study on the product you are offering. Ensure that your suppliers are genuine and offers good quality. You must know your demographics. Who are you targeting?
b) Who are your competitors and what are they offering in terms of price and quality?
c) Can you match that or can you afford to do a loss leading( getting your product out there at a cheaper price but quality & customer service will give you quantum sales faster.
d) Where do you want your presence? Online only or traffic from both online and walk in?
e) What type of funnel of strategy will get you there at the least cost.
f) Network--Network...Network. (Quality goods needs quality marketing)
A lot of time needs to be put into this.
There is a whole lot more but feel free to set up an appointment with me.
Best of luck.

There are definitely multiple ways !!
. Go to kickstarter and indiegogo and see if there will be backers or no
.Try to go for a roadshow and see if there will be a series A investors or no ( investors know alot about the market ! Even better than you sometimes)
. Check the comparatives / Competitors
. Do market research / study groups
. Go even to your future target customers , and see their input and hear from them
. Create an MVP ( Minimum Viable Product) and start doing sales. It is called MINIMUM for a reason

It’s pretty simple really, what you need to do is first determine who your customer is (by that I mean the person actually responsible for buying your solution).

Once you’ve done this contact people in your networks that you know who could be ‘the customer’ and pitch them the concept and assess the feedback and take if from there.

If you need anymore help book a call and am more than happy to go into details.

Pete

Create an MVP, that's why startups do this all the time. An MVP doesn't have to be a piece of software or technology, it doesn't have to be a functional site. Your goal is to test for market value, essentially, and find the people that would see value in this. You've already identified a target prospect in your question - small businesses that design and sell manufactured products. Ask yourself, how does your idea help them, and what sort of ROI can they expect.

There are a lot of resources online these days for getting contact information for such businesses. You can simply reach out and ask the business owner if it's something they would be interested in (and collect other useful feedback on your idea).

Otherwise I would suggest finding appropriate groups online, network locally, and basically just talk about your idea with as many people in the target market as possible. You can do all of this for little to no money, it's just your time, but this would be the simplest way I can think of to validate your idea. From there, if there is identified demand, you can look at building out an MVP and starting to get a user base you can grow.

Before you spend any money on even a basic prototype - speak to potential customers, what do and don't they like about their current providers? Speak to 100 creative/design businesses and look for common answers. Build a business around the most common answers with the highest revenue and growth potential. Read up on "Customer Discovery" to learn more.

Good luck!