Capture Paid Search Leads into and CRM Solution

Hey guys, I'm looking to spitball some ideas and listen to your suggestions. I have a client that offers a "service" and we are running a paid search campaign with Google Ads to generate leads. The campaign is setup to call his business for a quote or they can click through to a landing page and enter their contact information. It would be nice if this information could be entered into a CRM so my client can contact them via email or phone, and keep track of the lead. Most of the time he has to drive to the lead's house to gather information prior to giving an estimate. It would be nice to have a copy of this estimate attached to his lead and if the lead accepts, he comes a customer. It would be nice if he could also manage his customers, but this is not mandatory. He also doesn't need to accept payments or anything else.

It would be nice to have:

1. Lead Management
2. Customer Management - Once a lead converts, the ability to manage services by the customer
3. Employee Management so employees can be assigned to do the work required by the customer

My client uses QuickBooks so any integration with that would be a bonus.

Possible CRM Solutions:

1. WP ERP since they have a nice CRM module.
2. Jetpack CRM
3. Karrya
4. Hubspot
5. Salesforce

The main thing is the solution has to be simple! I'm not looking for anything overly complex or sophisticated.

Any suggestions?

It's been a while since I did this so the pricing might not be worth it, but I've helped a client do something similar where the leads from Google Ads was imported into Salesforce.
I used a disgusting match up of Zapier triggers/actions, but I believe there is now a native integration.

https://zapier.com/apps/google-ads/integrationshttps://support.google.com/google-ads/answer/6179720

I was thinking about Salesforce, but I fear it might overwhelm my client. Is it intuitive to use? Is it more geared towards marketers? I don't think they have a system in place to manage all of their customers besides QuickBooks. If there was a way to link the converts on the wordpress into paying customers in QB, that would be pretty sweet!