I stopped the water but the water spilt over and leaked through the floor down to the first floor.

I think a cleaner option would be you are basically earning income for renting out the roof space to a panel company. 

I did a nearly full rehab on the property including new roof, windows, flooring, and a lot more.

But if something is leaking, I can make a 30 second phone call to my handyman to go fix it.  

Maybe one has Hardie plank and one has vinyl siding and one has a newer roof and so forth.

With SF/MF rentals a major issue (roof, foundation, plumbing) could wipeout your profitability for a long time and your time will be consumed with dealing with tenants, toilets, trash, maintenance, etc.

Additional info - this project was spurred on by a terrible roof and even more terrible structural support under said roof so that stuff needed to be done anyway.

With over a decade in the roofing industry I've seen a few things and can help you with any roofing related questions, so please don't hesitate to ask!

Should be a good project, if I remember correctly it had a new roof and electric service and the interior had the bulk finished, and a new second mini kitchen. 

On top of that, we plan on adding a new roof and new siding.