Need a custom app developed for dynamic pricing based on quantity

[Cosmo]

Hello all,

I'm looking to create script, function, or app that adjusts pricing in my store based on quantity. 

I have custom price-qty-break metafields added to the Product object to specify discount prices based on quantities. 

When I load products via import, I also populate these price values (works perfect!).  

I'm able to write the code to show these prices when looking at my product page (works perfect!). 

Now I need to change the price in the cart based on the quantity (cannot figure out how to do this part). 

If someone is available to help me write the script (or write it for me and show me how it works), I can pay for the guidance and work.  

[Cosmo]

Thank you!  
I don't have a Shopify Plus account.  I'm a small business just getting my business started and can't afford that plan yet.  

The guide would be excellent!  I sent you a message for the guide.