u/CandyMoney1239

I bought a house it’s 12 20 ft.² and I’m adding another 220 ft.² onto the house. When I bought the house that had a brand new air-conditioning and HVAC system. It is 24,000 BTU 2 tons. Now that I’m adding on the addition they’re telling me I need to update it to 2 1/2 tons and redo the entire HVAC. And get a new air conditioner. I was quoted $20,000. That I know is egregious. Everything I look up online the most it says it could cost a 12,000. Can anyone give me some advice on what exactly this should cost? I have a crawlspace and an addict where the HVAC is. The house is only built in 1994 and I already replaced the HVAC in the crawlspace. Do I need all new HVAC for the entire house plus the addition any help is appreciated