Cost could change but the bigger issue is making sure the usage is still eligible for the type of policy you have.As an example, at the time of application, a company might ask are all lease agreements for one year or longer. 

And, if the money is borrowed and you lie on your loan application about that (they will explicitly ask and you will have to explicitly lie if you want the loan) then you're committing loan fraud.If you have to turn right around and sell this property for some reason, I,as the lender of the 20% down, will suffer a 50% loss. 

Do you think the tips in the guide, Real Estate Investing For Beginners, are still applicable in 2024 and beyond?

I would start the whole process over with the tenant - application, screening, and approval.

But he kept pushing, and saying that they don't hold my application until I decide.

Anything more than a small application fee ($200-$300) and maybe an appraisal ($300-$500 if residential) and I would look elsewhere.

DSCR would be your best bet but again 25% down and a DSCR of 1.25% minimum.Do yourself a favor and do not let just any Lender/loan officer pull your credit just so they can take an application and have a possible deal.

What are the key differences in approval times and application processes between private money lending and traditional bank loans?

Is a PM allowed to share the tenants application including credit reports and other info that is collected during the application process?

Perform the same task in each app to ensure a fair comparison.Load a property with pictures and details.Market that property.See what your marketing looks like from the public's perspective.Submit a fake application to see how easy the process is.Run a credit/screening report on yourself.Enter a maintenance request, assign a vendor, and attach a fake invoice.Enter charges to the tenant's ledger.Enter recurring charges and automatic late fees.Sign documents electronically.Run owner reports.After testing a few apps, one should clearly stand out.