11 y.o. Carrier Infinity Furnace went out. $105 trouble shooting fee.

Bid to replace circuit board $1600 (installed) Surge protector $230 (installed) and some wonky maintenance plan $200. From the original authorized Carrier installer, who installed it in in Oct. 2014. I diy'd it today for $650 (new circuit board shipped from Carrier via hvacsupply.com) and $80 surge protector. Located updated circuit board model from legacy board in unit. (Most supply places can cross reference it) Received it. Pulled small circuit plug from old board (which new main board said to re use on new board), put on new board to communicate with my Carrier infinity thermostat and I was good to go within 20 minutes. While I thought the $105 troubleshooting cost was worth it. (I.e. gas valve on these things are like $450 new or $100 on ebay). I wanted to cut to the chase as to what was wrong. Tired of a 59 degree house as well. But man, what a rip over what the industry wants. (I.e. $1800....fuck me!!)