How much will a 3.5 ton ac unit cost to install?

Between 8,000- 12,000. I put one in last year it ran a bit over 11,000 and from what I understand it has gone up 20% since then. Make sure your unit qualifies for an rebate. Your gas/elec. company has an approved list of dealers. I didn't know this until AFTER I put mine in and I had asked the salesperson about it before I bought it. I couldn't get the rebate.