How did you arrive at the specifics of you expenses? Did you get a trailing 12 or 24 from the owner/broker?
A quicker way to see if it works, is to subtract 40-50% of Gross income. You can spend lots of time analyzing all of the numbers, or just do a quick 45-50% depending on quality of unit and location and subtracting from Gross rental income to arrive and if it is a good deal or not. For example: i question your vacancy rate, your maintenance and repairs and your management fee (unless your including on site payroll into that). But all in all you are close to the 50%, so i would just use that number.
Secondly, might be tough to get a 30 year loan. Might be 20-25 years, also 4% is great. Might be a tad higher.
What you should do is analyze the deal in the best case scenario (that is still possible)
The worst case scenario, and then assume it will probably be somewhere in the middle.
I think you are looking at things a little too optimistic in this deal. You should be looking for value add opportunities. Can you increase rent? Why or why not? You can't decrease expenses because tenant already pays electric and gas. Its possible you could divert the water bill to them as well. You've already done the value add of laundry, and you can not get any lower vacancy (5%) is best case scenario in my opinion.
I would say no go. Good to best case scenario only 7.57% cap... i'd pass.
Also share the class and neighborhood class of this asset, it makes some differences