Gross net 13% return on investment.

he has the 3 missing packages and states they were delivered to the wrong address and that he is returning them.  

Even if he is 90% wrong that is still an amazing 1000% return from today.

When a child LLC (disregarded entity) is used to hold each property, and all of the tax reporting is done on the tax return of the parent entity, does each  individual child LLC need to file the BOI Report, or only the parent LLC? 

Strategies: maintain the most amount of credit lines possible without use; no late payments, ever; any credit that you do use as a consumer should be small relative to the credit limit of the account; keep your accounts open as long as possible; don't apply for credit unless you really need it to limit hard inquiries; space out any new applications or inquiries as far as possible. 

You may or may not wish to fix it since its likely too late to charge the last tenant's security deposit for it and also that it sounds so minor that people didn't even notice it right away.

Right, I asked for books and a schedule for the biz from the return.  

Very inexpensive cost for return. 

Quote from @Luke Machen: Hey all - I'm new to the RE investing game and have some (probably dumb) questions regarding cash on cash returns.

My Google research also indicated a lot of overinflated promises on monthly returns from the asset class in general.