But they will allocate their proceeds so that equity is concentrated in one of the replacement properties. 

The property is fully rented, close to University and a local hospital, which should support stable tenant demand. im willing to put 20% down payment, Im not sure about the costs that i should think of other than (management fee, vacancy, taxes, insurance , Maintainance) am i missing soething here (but Im saying 55 to 60% cost of the income).

FHA loans with low down payments are ideal for this.In the meantime, focus on improving your credit score and maintaining a solid financial foundation.

Some people don't have financial situation, nor have the bookkeeping to track or maintain it.Again, I personally find it very stressful just thinking about living that way for the life of the loan keeping the lowest daily balance possible. 

You need someone with a lot of motivation to maintain their OWN good record.

To thrive in real estate investing, you must maintain a firm grip on your finances.

To address this, request documentation, update the lease, address rent payment, consult an attorney, and maintain a positive tenant relationship by communicating clearly.

My ideal is to have a system or a standard in place to maintain discipline about procedures.

Giving someone control over who gets into my property while maintaining responsibility of kicking people out seems a bit risky.

The homebuilder could have figured it out how to maintain overall grading/drainage of the site, but it was more so needed to satisfy the City.