I've tried to monetize my product by implementing a freemium model, offering essential features for free while providing premium functionalities through subscription tiers, additionally leveraging targeted marketing and partnerships with influencers to increase visibility and conversion rates.
I had another thing going on. I was charging overcost for my expertise. It was working and I was making a lot of money. But as a solo developer, I couldn't take the strain, got tired and shut down my product at the very peak of its success.
In general, don't repeat my mistakes. When your product starts making any money at all, think about building a team.
@kmanjita in my case, the product is a photo background remover. There are many sites that offer this service, most of which offer subscriptions. For people adverse to ads, one of these sites is ideal. For people who are okay with ads, UnlimitedBG offers something nobody else is giving away for free - unlimited HD quality downloads and batch processing. Overtime, however, I could see offering an ad-free experience in exchange for a fee should enough users request this.