Find some reasons

like:
1) he paid late in June. Charge late fee. If he does not pay, start eviction process
2) refuse him to continue to fix up the house himself. If he reports any issue, you do estimate and hire others to do one small job every a week. If the issues are just cosmetic issues or just replacing too old items, refuse to fix.
3) If you notice any abnormal things around the house caused by him, send warning letter.
4) inspect the house every one month.

Little by little, you may collect some facts. I believe he will refuse to pay rent someday. Then you have facts to fight him at eviction.