Any help would be much appreciated I feel like I am spinning my wheels here. 

I have a custom object called Custom_Programming__c I have three fields on that object called Total_Hours__c and Custom_Type__c and Custom_Balance. 

when a user updates or creates a Custom_Programming__c record and there is a value in Total_Hours__c I need a trigger.

what the trigger needs to do is query the DAKCS price book and get two unit prices one for 'Tape Drop' and one for 'Custom Development' I am using this query to grab the information 

SELECT UnitPrice FROM PricebookEntry WHERE Product2.Name IN('Custom Development','Tape Drop')AND PriceBook2.Name='DAKCS'

The trigger will only fire if hours get entered or changed in Custom_Programming__c.Total_Hours__c

The trigger looks at Custom_Programming__c.Custom_Type__c and calculates Custom_Programming__c.Custom_Balance.

if Custom_Programming__c.Custom_Type__c = 'Bug Fix' or 'No Billing' then Custom_Programming__c.Custom_Balance is always 0.00

If Custom_Programming__c.Custom_Type__c  = 'Tape Drop' then Custom_Programming__c.Custom_Balance would be the UnitPrice of 'Tape Drop' + UnitPrice of  ('Custom Development' * Custom_Programming__c.Total_Hours__c)
 
and everything else would be 'Custom Development' * Custom_Programming__c.Total_Hours__c

**Note** 
values of the pricebook entries
'Tape Drop' = 750.00
'Custom Development'  = 185.00 

I have tried many different ways after watching many different videos so any help would be greatly appreciated.