The toilet doesn't flush or re- fill properly.

@Kellie Fernald Unless you are flush with cash, that volume of purchases might be a bit of a challenge.

There were many items I didn't list such as a $20 charge for getting the garbage disposal unstuck, or repairing a toilet seat that was falling off despite being a newly installed higher end toilet that was installed while they were there because tenants didn't feel the toilets flushed strong enough.

In addition to this you want to have professional paperwork in order which will act as a backstop should your screening fail to flush out a bad resident. 

Hi @Jonathan MariscalI don't recommend buying leads right away unless you are flush with cash and crunched on time.

If i understand corectly from your post and pictures, the floor is flush and straight, but you are concerned that there is a small space between the plywood sheets.If thats the case i would not do anything to the subfloor besides making sure that the plywood is properly screwd down to the joists and are not poping up, then just cover with the new floor.I hope this helps 

Also, as a new person starting out, they aren't flush with capital and a war chest from past deals.

One thing that I didnt see mentioned on this thread is that these units need to be flushed periodically. 

Others do it on site and you have to be careful of the way they dispose of their waste, especially liquid toxic waste.Some time back, I read of a lawsuit here in NY where the landlord and his dry cleaning tenant was sued over flushing hazardous materials done the drain, and then a sewer blockage caused contamination in the neighborhood when there was wastewater backup.

Here are some examples:Example 1- A hollow core door or doors which do not contain fire rated glass must be replaced with a solid wood door flush at 1 3/4" to 1 3/4" which equals the equivalent of a 15 minute fire rating.