Internet service for calculating the cost of house maintenance

The service should allow real-time creation of estimates of maintenance and repair of common property in an apartment building, determine the total cost of work and calculate the cost of monthly maintenance per square meter of total area.
There is a list of standard works (1 table) from which the user chooses the work, enters the amount of work. Based on the data entered, estimates are generated.

The main features of the service:
- Calculation of the annual cost of maintenance of the ICD;
- Calculation of the cost of maintenance of 1 square meter per month;
- Formation of the form for printing;
- Preservation and loading of estimates;

I am waiting for your proposals for the cost and time.

Preferably, the service has the ability to be integrated into an existing site written in WordPress CMS. Options that it will be a separate service not integrated into the site are also considered.

The design is attached, but in principle we discuss.