I don't see where it changes the lease or rental agreement in regards to your ability to evict the tenant in case he turns your rental unit into a petting zoo or prostitution business.

I'd rate myself pretty high on the DIY ability scale but it was rather easy and I think that most DIYers could install these systems after watching a YouTube video or two.

I am wondering if my investment property will effect my ability to be approved for a mortgage on my future primary residence given that timeline, thanks!

As you mentioned, there was an element of both luck and a good deal (though it's a 200 year old house, so the major improvement pains are yet to be seen...the house was greatly maintained and updated by the former owner, thankfully). 

Doing your own work is always great if you have the time, money, and ability.

But that's TV, and to make (big money like you refer to) in Real Estate it takes specialized knowledge, TIME, and Money as well a the ability to handle Risk without breaking down mentally or emotionally....I'm not saying you can't do it--you certainly can...but it will most likely take time (in addition to your practice) and sometimes stress and TIME combined working at it.How long will it take...unknown.

If we did win the bid do the current owners have the right/ability to stay in the house?

If you have the ability to borrow, use someone else's money (ie a bank's). 

You'll probably need a new gas valve, so expect a bill for $300 or so.

With today's technology and tracing abilities I go after them hard for what they owe me.