You already asked in https://www.cnet.com/forums/discussions/advice-for-startup-outsourcing/ so I'm locking this duplicate post. Please continue there.

You really have to be more clear about your needs. Both 'software services' and 'business processes' relate to running a business, while 'projects' relates to making or doing something new or in another way.

Also, please make clear why you found all freelancers to be unsuited to be a trusted partner. What are your minimum requirements for a service provider to be trusted by you?

Forty years ago, a common saying was "You're never fired for buying blue." That is, for buying IBM, very reliable, very trusted.
I doubt if it's a good choice for a startup, but why not have a look at https://www-01.ibm.com/software/sw-services/ ? it might help you to get a better idea of what you really want.