Quite honestly, as a landlord or landlady, you really don't need to know much about CONSTRUCTION. The vast majority of the work we landlords do is MAINTENANCE and REPAIRS with lots of CLEANING thrown in. And, unfortunately, because of the very broad spectrum of knowledge we need to have, there simply isn't any "training" you can take to become what essentially amounts to a combination handyman/lawyer/accountant specializing in insect control and appliance repair.
What I'd recommend you do is buy a good quality DIGITAL camera and open a free account on at least one photo hosting web site like w w w.photobucket.com
Image hosting, free photo sharing & video sharing at Photobucket
so you can post pictures for other people to see there. Then, just Google "DIY Q&A forum" (without the quotes) and you'll find lots of DIY web sites just like this one where you can ask knowledgeable and experienced people about specific problems you're having and show them pictures of the problem so it's easier to communicate. That's a far more efficient and effective way to get the knowledge you need than to learn a bunch of stuff from a training course and then forget most of it because your mind realizes it's not using most of that information.
(Your brain is good housekeeper. It throws out information it doesn't use, even through it knows it might need that same information at some time in the future. So, taking a course in stuff you might need to know isn't a very effective way of learning because you forget most of it by the time you need that info. I'd say, try using the latest technology available, the internet, to get the info you need at the time you need it, just like you're doing now.)