Selling a building with further long-term lease

Selling a building, privately owned land, a multifunctional complex.
All communications are connected, electricity is laid, the floor is tiled, the heating unit is assembled and functioning, ventilation and a separate air conditioning system are installed, and much more is already in place.
We are ready to enter into a long-term lease for 3-5 years as we did everything for our projects by concluding an agreement with you on the terms of a 7-8 year payback of the property for you as the new owner.
The project was laid out and made taking into account the launch of a car wash, a computer club and a cafe. There are already sketches and projects. The construction process is at the completion stage and documentation is being received.
About 70 million tenge were invested in ventilation and air conditioning equipment alone (call your specialist and compare prices), everything was done for yourself, the materials and equipment were of good quality (during the inspection, call your specialist/technical supervision, etc., make sure). Heating and wiring with a heating unit cost about 45 million tenge (you can also check everything and compare the quality-price ratio on the market) A promising, densely populated area.