Am I missing anything?

I find this tmobile reddit very helpful and learned a lot. Today, we are going to Costco to switch from ATT to Tmobile. We have been ATT customers for 15+ years. The reason we are switching is because $1000 off Iphone 18 pro. My wife has IPhone X and I have Iphone SE. We get only $20 to $25 for trade in for them. My daughter wants a phone for the first time. We will save $3000 for 3 Iphone 18 pro. Here is the math. Let me know if I am missing anything? Costo Rebate: $1200 ($400 per line. One is $250 and the other one is $150. One rebate the sale rep submit and the other rebate I have to submit? We won't get the rebate after 14 weeks.) Activation Fee : zero (Costco waived the fee. We will save $105) Shipping: It will take 2-3 business days to arrive. Costco don't stock Iphone. Experience Beyond monthly plan: $170 (3rd line is free) before autopay and taxes and fees Taxes and fees : $24 ($8 per line -this is what we pay at ATT, Tmobile might be higher or lower) Iphone prorated: $16.67 ($200 divided by 36 months = $5.55 x 3 lines = $16.67) Total monthly: $210.67 before autopay with debit card ($5 per line) Insurance: $??? (how much per month and it is worth it?) Hulu with Ad on us: $0 Netflix with Ad on us: $0 Apple TV: $3 per month (we might not add this because we don't like any shows) Ask for code (employees only get so many every month). We do have Work perks (teacher discount) but work perks and 3rd line can't be used together. Best to have 3rd line free. Yes. We missed out on the $1200 off Iphone last month. We were going to wait till Black Friday to sign up but with Tmix coming. It is best to sign up now. Thanks for reading this, let me know if I am missing anything.