Outsourcing software development can be difficult. Here is a good article that covers many of the issues you are likely to encounter.
In my experience, finding good developers is very hit and miss. I’ve found that a $100 per hour developer can be much cheaper than a $20 per hour one if you find someone good. A higher price doesn’t always mean better, either.
The costs and difficulties associated with outsourcing development are a key reason the no-code movement is taking off. Tools like Bubble, Airtable, and GlideApps are taking a lot of the specialized skills out of software development.