Can I changed the lock and restrict her access to the property since she broke the lease?

We rehabbed both units to include redoing drywall and insulation, refinishing hardwood floors and adding LTP flooring, adding a new bathroom vanity, replacing some fixtures, andredoing the front deck and adding the back deck for separate access to the back unit.

I rarely need a contractor and if I do need one, my network has access to skilled workers. 

What kind of Lead Generation Tools will I have Access to?

You are prevented from doing/ accessing a lot of useful things if you aren't licensed though.

Basements in older homes can be problematic - ceiling heights, fire separation, access to sewer above grade etc.

So I was able to use my credit score to access 0% interest credit cards.  

Forgive me if I missed it, @Justin Johnson but do you have something in your lease regarding unauthorized occupants? 

So prior to this text he and I had briefly chatted about investment rental properties because it was something he brought up and the conversation more or less was "this is what I'm doing as an agent because I have access to the MLS  to see what's coming up before the general public and have you guys ever considered real estate investing?" 

The area is always expanding the business district as well as downtown, from Access to low cost regional talent, competitive real estate cost, strong work ethics and excellent facilities for sports, shopping, leisure and healthcare.