Hi there, I submitted an Inland application in August 2020. My spouse sponsored me and we prepared the documents together. While it is possible to prepare the documentation on your own, I have seen people's applications returned for many minor issues (that could be fixed with an email correspondence, for example). Given the delay of processing due to the pandemic, I regret not having someone at least look over my documentation.
If you guys can afford it, I would recommend you have a paralegal look over your final application package. Paralegals are typically less expensive than lawyers and you would at least have the peace of mind when you submit your application that you haven't made any "silly" errors.
Any applicant should triple, quadruple check their app before submitting.
Unfortunately lawyer or consultant is not a guarantee of no mistakes - as multiple cases here attest. Applicant remains responsible if any mistakes,omissions, or misrepresentations.
So sure, for those who wish to have a third party to check, by all means. Or simply for those for whom the aid in completing is worth the money.
But again - don't rely on those third parties. The applicant bears all the responsibility. Check carefully.