Greetings,
Thanks for considering me to bid your project and to work with you. I have gone through your requirement by visiting your sample sites. with an initial analysis, I found that will take around 70 to 80 hours with design and development with required implementation. But your budget is mocking up your requirements. It is really too low even for just design.
If you'll be really able to go beyond your budget or clear about your requirements, I would love to work with you. with complete mentioned requirements can be done in $2000 with fix budget.
I'm still available to discuss further price can be negotiated with some realistic terms. I'm flexible with timing for you.
Thanks,
Ahmed