Generally, no nightmares, because I told all potential tenants right up front, “I am calling your prior landlords, I will not accept any evictions or criminal background more than the occasional speeding ticket”.

I occasionally see "opportunities" to purchase real estate at stupid low prices $500, $1000 or even $1.

Do you occasionally get lucky and have a home fall through the cracks that you can pick up for close to opening and do pretty well on it or is it so competitive that you pretty much plan on every home getting bid up within 10-20% of ARV?  

You should also consult with a Tax Accountant occasionally to see what opportunities your are missing out on to legally record expenses.  

That would reduce the revenue and eliminate the possibility of having it occasionally available for the in-laws, but at least it would be a viable "out" to recoup the initial investment.   

Occasionally people will put their off market deals on there.

A wholesaler (and occasional rehabber) I recently talked to said he has scaled down his advertising because he is getting so many leads that he doesn't have enough time to set appointments with the qualified prospects.

Occasionally you'll find one that's a mess.

visitor and occupant are difficult to differentiate because you are not there 24/7, a son visiting an aging mom every day and stay late on some days to care for her and occasionally crash on the couch is not an occupant but he might have her keys.Its best to have a talk with the tenant and set the expectations up front.If its up to me - but its not :( - I prefer no one except the ones on the lease and be notified and obtain authorization anytime anyone else is going to spend the night.

If you let investors here on BP know what market you will be investing in, then there is a very good chance that someone will be willing to assist you with trustworthy contractors and property managers, maybe even an occasional drive-by of your property.