I use this app myself. Worst case, if it fails as a business I open source it and continue to use it myself (after consolidating onto a single host just for myself).
And I'm in the US and not going to run out of money assuming I can keep my day job :)
- Maintenance costs will be a limitation on how many different experiments you can keep running at the same time. If you consolidate everything on the same machine, and still has 98% of the machine for the next experiment, you will keep your first one running even if it has low profitability. If you need $120/month just to keep it running, you will be tempted to close it down after any new idea appear.
- You are assuming that the OP lives in a developed country and has a well paying job there. You are also assuming he has no risk of being unemployed for a couple of months.
- All that is probably dwarfed by taking a couple of hours a day for reading HN. So I should go back to my project and stop thinking about unasked advice :)