I have a 25 HP tiller outboard that only start if using Starting Fluid, it stalls if you don't keep spraying the Starting Fluid.
Had the motor serviced with the following work.
-Cleaned the Injectors and Fuel Rail
_ New Fuel Filter
- New High Pressure Pump
- New Low Pressure Pump
I'd return it to whoever worked on it. Sounds like you spent a ton of money for someone to tear up your motor. What year is it? Why did the mechanic think it needed all those parts? Why did he let it leave his shop in that non-running condition? I'd get some/all of my money back and take it to someone else. You obviously have a fuel delivery issue.
