Using the cashflow you provided indicates a 21% ROI based on a sale price of $420,000. However, you noted that there is just 19 months left on the lease and the option rate must be negotiated so that's an unknown. The current rent is running at 24% of gross sales. Utilities are running about 20% of gross sales. Also, the labor cost of $2,000 (13% of gross sales) is low unless this is an unattended laundromat. If you will not be doing your own machine repairs, the $300 repair labor cost is too low. A lot depends on what your business plan will be, what your competition is like and what your market looks like. Without knowing these things, it's difficult to gain much insight here.
"Lead, follow or get out of the way." Larry Adamski
I have not looked at anything past the word lease deposit - because none of that matters.
It sound to me like you are renting a business for 18 months for over $400K. Often times options are not transferable to a new owner, which means you could loose everything in 18 months. A rent increase of 4.5% a year will kill you. In ten years your rent will increase by 55%, plus increases in CAM costs. Further you have no clue what the rent will be in 18 months, even if they extend the options to you. Could be the same, or could be much much higher. They can charge you anything they want, and you have no choice. They know it would cost you a fortune to move, so beware.