What would be the best way to signup local businesses to a new influencer marketing platform?

Having sold to these businesses in a variety of capacities I agree demonstrating the value and benefit to them can be quite challenging. The smaller a business is the more cautious they will tend to be with their limited marketing dollars. My advice is to focus on low risk strategies where you offer value without commitments from them to build a relationship. Make them give you a killer offer to maximize the effectiveness of your campaigns (Free is a magic word). Once they see the direct response to your efforts let the fear of loss do the selling for you. Also ATTRIBUTION (think tracking) is key to getting past the hook point. I may be of service in refining your pitch. Thanks!

Nice question.
Here is what I suggest:
1. Select 10 local businesses. Offer them 1 FREE* endorsement (see next comment).
* If this is too expensive for you, you can always add a condition that if the endorsement brings them more than x new customers, they pay the initial cost of the endorsement (so no profits for you, but it will cover your costs).
2. Have a local influencer endorse the business and make sure to track/measure (and photo) the positive affect. You offer this free for those first 10 businesses, on the condition that if it works they write you an amazing recommendation (you can even draft the recommendation and show it to them in advance so they approve it). Be sure to ask the influencer to mention a specific discount code so that you and the business will be able to track the success of the campaign.
3. Now, when you go to other / new businesses, you show them the proof that your method works (the letters of recommendation from businesses).
Make sure to have a short, simple, agreement with future clients. I've successfully helped over 300 entrepreneurs and I'd be happy to help you with the business and legal aspects.
Sounds like a cool venture. Good luck

If you believe local businesses are hard to scale, have small marketing budgets, ehy are you targeting them?
1. Your presumptions about local businesses are inaccurate.
2. Hire someone experienced and successful selling to local businesses to
guide you and your team.
Beware launching a company in a niche that is not your domain - bring help on board stat. If you'd like to discuss how local can be lucrative, I've advised locally focused startups.

If you really are a true influencer, then people will contact you with offers/post they will pay for your posts.

Better to work on you influence (building large followings) than go after uneducated small businesses.

Time invested building audience will pay off way more than time invested educating uneducated people.

Best to always focus on highest net return work.

Great tips already! In short, when your offer gets them to think, "I'd have to be nuts to not do this!", you've got an offer. If you're thinking, "but I'd go broke", but you already are, nothing to lose.

Agreed too, stay away from the education game. Marketing means differentiation among competition, otherwise you're educating on why they'd want to buy at all... equals broke. Apple was in the education game, dying, until IBM entered the market, Apple celebrated the 1st competitor: https://www.inc.com/bill-murphy-jr/37-years-ago-steve-jobs-ran-apples-most-amazing-ad-heres-story-its-almost-been-forgotten.html Competition makes you grow!

What's your USP? Start there. Read this article, it's pretty good because I've contributed to it. ;)