I would suggest to start researching Idealista, however even before that thinking yourself where you feel comfortable to invest and what your investment plan would be.

I would put the student loan on an automatic minimum payment plus some comfortable, but not too large, additional principal payment (if available) per month, then forget about it.

look at your experience level with reality in mind.I would want to feel very comfortable about those things before spending time on deals and money when i had no real capacity to transact no matter who the lender was.

You will do better door knocking when you feel comfortable, and when you feel comfortable the people in front of you will feel more comfortable and they can tell (but we should also not feel like you are dressing for your living room either), and so dress how you would want to dress, in a way that is clean, professional, but more casual in clothes that fit well and are not uncomfortable to tight or too big--  otherwise you will feel it as soon as you knock on the door.  

If I buy these lots—7,500 square feet with a 50’ width—how comfortable can I be that the person who buys them from me will be allowed to build a house on them?

If you want to be generous about it you could tell the tenants your operating costs are consistently going up (which is true), share the current comps with the tenant, and ask them what kind of increase they would be comfortable with.What are peoples’ thoughts on where rent’s should be set or the best way to get them up if you fall behind?

I needs to be comfortable for the group.You need to decide what your demographic is.

Get out of your comfort zone.

They aggressively de-lever to not only create more cash flow without having to buy more assets, but also because they are starting to think about estate planning and how to efficiently create a very comfortable life for their kids.Lots of debt, long term debt or no debt are all right answers.  

It’s important to ensure that you feel comfortable with the team members they provide.