Web App Hosting model

Hey Indies,

Asking for opinions/experiences/thoughts to this savvy group of devs. I do some freelance work on the side building MVPs or proof of concept apps and I want to include hosting services after I finish the app to get recurring revenue. Are there anyone here providing this and what model do you use? Any recommendations?

I currently use GCP for my apps (dockerized in cloud run). I'm very familiar with it and so far has given me good results. Haven't tried other like AWS, Azure, Digital Ocean or Heroku. So, models I had in mind were:

1. Charge a fixed amount/month for a fixed amount of usage and an extra rate in case the app goes over the fixed amount. This amount would include hosting + support.

2. Or, charge at the end of the month what they consume + a profit margin on top. This would be after the month is over and I can calculate how much has been used.

From a cash flow perspective option 1) sound better as I always know how much is going to come in.

What do you reckon?

Thanks in advance! :)