Also, to answer your question, I'd check out Jason from saastr.com. He has some good posts on how to hire your first few sales reps. One big thing to check is if you would buy your own product/service from them as a founder and are they truly interested in what you sell to the market. Here's a link to post he made on this https://www.saastr.com/that-first-magical-sales-rep/. Source: over 1 year ago

Here is my product: https://matchkraft.com/. It is a marketing toolkit. I think you need to ask for feedback, asking why users don't want to pay for a premium subscription. So far, you are getting new users that is a good sign you are going to the right direction. Maybe, who is your ideal customer or maybe your product is ok but need more visibility (maybe paying ads). Try to get active users. I really want to... Source: 12 months ago

Calling a 3rd party API: There is a complete ecosystem providing "google-sheets-as-DB". I personally tested and recommend https://sheetson.com/ but there are a lot more with free tiers https://sheetsu.com/ https://sheety.co/. Source: about 2 years ago