How to raise roof of 1978 manufactured home

[Lzbcn0]

Hi all,
I am a first time buyer of a very old 1978 manufactured home. It has very low ceilings (6’4”” to 7’5”). I want to raise it to at least 8’ to 10’ in the middle.

Can it done? How much will it cost? Can I do it my self?

Also, I like to add a bathroom to existing structure. How do I go about doing it? Do I need an architect to build a blueprint first?

I will appreciate some help.

Thank you,
AA