-------------------------------------------------------------------------------------------------------Recommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

I would review your process with how these investments are going so far and figure out what's working and what's not.

Then you owe hime another $40 to $100K depending on how you figure it out. 

I curate a list of properties priced under $800K with the potential to generate six-figure gross income and share it with my clients.

----------------------------------------------------------------------------------------------Recommend you first figure out the property Class you want to invest in, THEN figure out the corresponding location to invest in.Property Class will typically dictate the Class of tenant you get, which greatly IMPACTS rental income stability and property maintenance/damage by tenants.If you apply Class A assumptions to a Class B or C purchase, your expectations won’t be met and it may be a financial disaster.If you buy/renovate a property in Class D area to Class A standards, what quality of tenant will you get?

I compile the list of only properties that can gross six figures plus and with prices under $800k.

This fire, these homes, these people, hard pressed to find anyone getting anything less than 7 figures, significant 7 figures.

I offer an online payment portal to submit rent payments via ACH or CC - they "couldn't figure out how to use it" so I set us up to accept Zelle payments.

@Andrew Steffens the pool of buyers that have six figures of cash (you really need about $150k in cash to buy a $500k STR), have some subject matter expertise, AND want to self manage is even smaller. 

It is a get rich slower scheme, but with less risk.How do you figure a paid-off property throws off more cash (per month, yes, but in comparison to how much you put down?)