Since, market research is utmost important for any new business venture, initiate both primary & secondary research.

Secondary Market Research: The parent industry always plays crucial roles for its downstream. So, understand the industry statistics and various other parameters like industry size, industry challenges, current and likely future trends/changes, technological innovation, similar offerings/players profile (if any), industry appetite for new offerings, etc. In other words, identify various important parameters like latent demand of something of this kind.

Primary Market Research: Understand the gap which is needed to be filled up in the industry and come out with an appropriate plan of action.
This would help to validate if consumers are interested in a commercial product and identify if consumers will pay for that product and for how much. Finally, to be able to decide whether or not to launch your business.
Here, critical considerations are- questionnaire design/survey programming, sample size, sample selection procedure, data collection method (F2F, CATI, Email, Web Based, etc.), data tabulation and analysis.

Costing is a concern but phone survey would be preferable than email for sure.

I can help you with entire process, if interested.