It depends on the dealer and the manufacturer. Different manufacturers will have different definitions of what they consider a shell. Assumedly, it will have all the necessary bracing and windows, but that is really a question best answered by the dealer that has the trailer. Just ask them to be more specific.

Edited for spelling

Usually the shells that are purchased with the idea of having a LQ added later can include many options. The floor joist spacing will be set up for the placement of holding tanks; a camper window can be installed if the purchaser wants it; as was stated, ceiling bracing is added for a future A/C, the bunk area will have an emergency egress point, whether it is a larger over head vent in the bunk area, or special windows that allow egress. The door will be "camper" sized and will probably include a screen door.

The spare tire can be externally mounted as some are carried inside; a shore line power cord and central electrical box can be installed;  a shelf and bracing for the propane tank(s) and battery (ies) can be welded in place. Heavier axles and tires can be ordered, power jacks can be added, it's easier to install an awning before the insulation is installed, along with any optional exterior lighting.

The more you have factory installed now, the easier it will for the conversion company to complete your interior. For instance, if the LQ company had to cut out your sidewall, add additional bracing and install a camper window, their efforts would be more extensive than the factory installation, while the trailer is under construction..

Gard