I'm having a concrete patio installed in our backyard. The HVAC condenser needs to be moved. Seems this would require:

Properly evacuate the refrigerant (R-410A)

Disconnect

Move (I can do this)

About 10 days later:

Reconnect

Recharge with same amount and same type of refrigerant

If it matters, it's a 4-ton system. Very easy to access all connections.

What's a reasonable cost for steps 1, 2 and (10 days later) 1, 2? I feel like I should have a contract, in writing, on what's expected. I don't want steps 1 and 2 done, and then never see the AC tech again for the remaining steps. Also, we're headed into summer, so this will likely jack up the cost.

I considered the DIY approach with a refrigerant vacuum pump kit from Amazon . Though I'm technically pretty skilled, I'm worried I'd mess things up and have a much bigger expense on my hands.