Dear Sir,
I've read your project description and I'm so much interested in your project.
I am a senior web developer and I have 10+ years of experience in web development.
We can setup captcha on your signup form.
If the Interspire provides a way of integrating captcha by a plugin or an extension, we can install it.
If not, I am sure I can install Google Recaptcha on your signup form.
I hope we can discuss more details in chat.
I'll look forward to hearing from you soon.
Thanks so much.
Kind Regards.