Replacing stock 6x9's with 6.5 speakers (transfering my whole system)

[fromhailey]

My car was totaled and I removed my stereo system to install into the new car. The set up is 4 6.5's, dual 12" sub, 5 channel amp, double din reciever. The car I want to buy is a Toyota Camry with stock setup of 4 6x9's and 2 tweeters. I have read that it is possible to put a 6.5 speaker in to replace the 6x9, with special mounting and adapter. I will have the installation done professionally, but they are closed due to 'stay-at--home" order, and i would like to get some answers now rather than wait (to help my car purchase decision). Do professional installers do modifications like this (like CarToys)? How many other peices of the system does it effect? For example, does this require special wiring, or is there a component I'm unaware of. How much extra is this cost besides what it would already cost to install? or should i ask, would the cost be reasonable?

[Dafaseles]

I guess it depends on where you go, though I've never heard of an installation shop that couldn't do that. And I wouldn't think it would add massive amounts of extra labor to the cost. No special wiring. Just either a premade mounting bracket or they'd make their own. 

[Ron36]

Why have a shop do it when it’s on Amazon for under $20 bucks 

[Dafaseles]

41 minutes ago, Ron36 said:

Why have a shop do it when it’s on Amazon for under $20 bucks 

He makes a good point