I would suggest you send written notice to terminate the contract based upon their negligence for approving that repair without your consent.  

The goal is very big for starters, but I implore you to plug into my example the requirements of only doing 1 deal every 3 months or 6 months, you will notice the amount of money required and amount of houses required greatly reduces in that case. 

I noticed both lenders want 25% and I’m confused as to why.

I have noticed a property in my neighborhood that has been empty for about 6 months now.

Sloping and mortar cracks as well as noticeable settling are all common.

Can I give them 30 days notice with cause, (the drug charges).

(Pro tip: No one is going to sign a rent increase early.)If they are on month to month leases or informal, verbal leases, present them with notice in accordance to your state laws that says you will be increasing rent to $X on whatever date complies with the laws.Note that a 30-day notice isn't 30 calendar days, it is 30 days including one entire rental period, so if you give notice before June 1, you can increase rent on July 1.

The tenant that was there at the time was nice and we talked about whether or not there were issues with the property that he noticed (none) and that specific neighborhood in the city and he also mentioned that he was planning on renewing his lease in a couple of months when it’s up.

If you want to keep them put them on a month to month lease and if they do not move out by the fall I would give them the proper notice that you are not renewing to get them out.

Then give them a months notice to vacate.