I've put Mobile Joomla! on more than one website with no problem.
Then I hit this one. They are using "Multi-Site". Is this a problem? They are also using SEO links with the modified .htaccess. Is *this* a problem?
Here's the install log below (errors):

JFTP::login: Unable to login
JClientHelper::setCredentialsFromRequest failed
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla 'mobile_smartphone' template.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla 'mobile_wap' template.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla 'mobile_imode' template.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla 'mobile_iphone' template.
Rename failed
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla modules.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile Joomla Plugin.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile - Simple.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile - Always.
JInstaller::install: ERRORXMLSETUP
Unable to detect manifest file
Cannot install: Mobile - Domains.
joomla
Any help you could give would be very appreciated.

Joomla 5 Page Website
Traditional Site
No CMS Price
Range$300 to $500

In here, you will offer your client a traditional 5 Page Website, but you will hide Joomla.
What about if they found out you are using Joomla? Well there are ways to hide Joomla. Like disabling the Administrator Control Panel and eliminating the Joomla Generator Tag.
Also being honest from the start is another option. Just tell him that it is a Joomla Site.
However what I will recommend you in here is setting your prices from the beginning just in case he wants you to show him how to edit the site.
If he wants to take full control of the site without paying you for the training, make him sign something to make him responsible just in case he does something wrong while editing the Joomla Site.


Joomla 5 Page Website
CMS Site
CMS and No Training
Range$800 to $1500

In here, you can give the option to your clients that you can build them a CMS Website where they can update or add pages by themselves.
However if they need training, you are going to charge them by hour or by a fixed price for 5 to 10 hours. Work with their needs.
Mention him that it is a Joomla Site.
What I will recommend you in here is setting your prices from the beginning by hour, by video, or one on one training.
If he wants to take full control of the site without paying you for the training, make him sign something to make him responsible just in case he does something wrong while editing the Joomla Site.

Joomla 5 Page Website
CMS Site
CMS and Training
Range$1500 to $2500

In here, you will offer your client a traditional 5 Page Website, but you will hide Joomla.
What about if they found out you are using Joomla? Well there are ways to hide Joomla. Like disabling the Administrator Control Panel and eliminating the Joomla Generator Tag.
Also being honest from the start is another option. Just tell him that it is a Joomla Site.

However what I will recommend you in here is setting your prices from the beginning just in case he wants you to show him how to edit the site. mobilejoomla / 
domain / If he wants to take full control of the site without paying you for the training, make him sign something to make him responsible just in case he does something wrong while editing the Joomla Site.