$300 for custom work - I need a good dev

I contacted the os solutions team and asked for some custom work.
They dont want to do the job as they are too busy

Is there anyone out there than can do custom work on the shopping cart?
I will pay 300 dollars for some changes.

I need the USD value to state the RBT value so that there is NO misunderstanding that a user is buying RBT at (for example) $0.02 and so on
so if you click... add to cart...
I need a drop down from $5 to $250
with the conversion of 1 USD to Rimbit being calculated from rimbitexplorer.com/q/getrimbitprice (dynamic)

So if someone buys 100 USD worth of RBT at $0.03, it shows that on the cart, is sent in the invoice and is also displayed to me
BECAUSE... the valuation goes up every 24 hours
and a delayed payment may mean I charge at 0.03 instead of 0.02

Hi,
Just want to let other developers know that Mark found the developers to work for him.
Mark: Hope that everything will be done well with you.
Sincerely, Giang