Yes, GML can produce all the necessary drawings for your modular building and make an application on your behalf. We could carry out these works and prices range from from £750 - £3,000, dependant on project, plus the cost of local authority charges subject to the complexity of the project.
Yes, foundations are needed for all modular builldings, but these can be minimal with this type of structure and are usually individual pad foundations, subject to local authority approval, which can go straight onto an existing surface. Alternatively, modular buildings can have a concrete footing set into the ground, which can usually be contained to a depth of 600mm.
Yes, you can design the internal layout of the modular building yourself and have partitions exactly where you require them to be to give the overall room sizes that you need. The only constraint is that the overall footprint of the building has to link up with / be in line with / module sizes.