Unless you are a extremely naïve person having a tenant that smokes means that they and their friends are smoking inside your property.

This also means that the new well cost about $22,000. 

Not meaning to post duplicates but I can't delete this one

I mean I understand that if I invest $1000 and make $100 over the course of the year then I got a 10% return. 

As for the leak you have the right to repair your home so you can simply say the plumber will be here at 2pm tomorrow and you can let the plumber in. normally  the tenet has the right to live in peace meaning that you can't just come over whenever you want but that right is waved when you need to repair your property.

A CPA did my taxes but he basically just fills out the forms if you know what I mean.  

It's always hard to get mean spirited comments from tenants when your intents are well meaning ... that's part of the deal with property managing your own properties. 

It provides a means to not provide answers to requests immediately.  

Not sure what you mean by "I can’t seem to understand the 50% rule if I decided to put only 5% down..."

Just because it sold for 35 means nothing.  35k + 25k rehab + 10k profit to TK company = 70k