Build a Property Maintenance Webapp + phone app

I need to create a software fro tracking maintenance requests for different properties. Must have features such as users, reporting incidents, our company staff able to respond and take pics when reporting to an incident. Basically it is a ticketing support system for properties. Also need to be able to add lists and generate simple invoices for client approval. Must have multi users with different layers of permissions. Potential to further develop in the future

Looking for someone who has a similar software created before that can be modified and adapted to our purpose.

Please provide an approx range (even if it varies) with your proposal . If you have a demo or screenshots of a similar project, you will be highly considered