OK. When you go to Sonic, use the new drive-thrus. Management times these, and the service is faster than pulling into a slot your truck can't fit into, anyway.
Go on Tuesday after 5:00. This is when they run the #1s half price, or buy one, get one, depending on your accounting esthetics.
DO NOT let them talk you into putting cheese on the burger! This is an extra dollar, and you're driving these burgers home anyway where you already have cheese looking for a raison d'etre.
Here's where the math gets a little tricky. You clearly don't want to eat two separate hamburgers (how bourgeois is that?)
You want to pick the best top bun, the best bottom bun (yes, they differ in quality). You will use the second-best bottom bun for the middle, as you're essentially recreating the Big Mac.
Extract the two pieces of meat, cover with cheese, microwave, and re-assemble with all the lettuce, tomatoes and onions for one bigass burger.
Your cost: $3.50 including the tip for the carhop.
Bet=but
LOL! As if.