Concerning the signature of the contract for work, should the city be adapted to the city of the contractor? Who should sign on the following lines? Is any stamp needed?
Yes, you can adapt the city to the city of contractor (although it would be not considered a mistake, if there is Prague). The contract should be signed by a representative of your office, meaning by a person who has a mandate to conclude a contract on behalf of your office. So, insert the name of the entity entering the contract and the name of the person signed. Include a stamp (although it would not be considered a mistake, if there is no stamp).