In conducting the commuter survey according to Option 3 / Approach 2 I am would very much appreciate your feedback on the following topics.

The multifunctional building is occupied by 1250 regular occupants with 20 tenants.
1200 regular occupants are located in the office area, while 50 regular occupants are employed in the shops and restaurants.

The building is located in the very centre of Hamburg and we expect a RCCT reduction by >70%.

We will conduct an assessment using Survey Monkey and approach 470 regular occupants. There will be two different surveys for the office occupants and those employed in the shops and restaurants.

I have the following questions

1) Statistical validity of survey participants: would it be ok to approach one or two of the 20 office tenants and have them distribute the survey to all of their employees via a link to survey monkey? Since the tenants distribute the survey to all their employees the selection of participants is representative. The scope of business of the tenants does not indicate that their employees would have a preferred choice for the means of transport.
2) Since the return rate is crucial for the calculation of the reduced RCCT, I am wondering which other ´documentation´ than my statement regarding the number of employees is required when specifying how many regular building occupants received the survey? The online survey will be distributed via a link, the report generated by the software hence cannot document how many persons received this link.

I am looking forward to hearing from you