In this post, I'll provide a general comparison between the main types of mobile homes.
The brands and their prices you can select for your mobile home will mainly depend on what vehicles were sold in your country, and the quantity thereof (as more vehicles of a certain type were sold, the price will be comparitively a lot lower, especially when buying secondhand -which is what you best do-.
Below, 2 main categories are made: "original vehicles" and "customized vehicles". Both can be bought second hand obviously, but the customized vehicles will have been made to suit the original owner, so may not be designed the way you like it (then again, sometimes it might).
Also, the customized vehicles may in some cases be much more expensive, just because it was custom-made (mass-produced vehicles would have comparitively much cheaper to produce). That said, these are assumptions, and whether it's best to buy an original vehicle or a custom one will depend on what's offered at that moment in time, in your region.
Also note that the price of the vehicle will, besides the brand/model, too depend on the state, and age of the vehicle. If the vehicle is say 5 years old, it will all ready have decreased in price by 29% since the first year of being second hand.
The prices mentioned below were checked with eBay and are (as mentioned above) only indicative, to allow comparion per class of mobile home.
Note that you should also take into account the requirements per class: for example, to drive a large bus or a housetruck, you might need a different drivers license than for a minibus or to just tow a trailer. Sailboats and houseboats can also only be moved if you have a maritime certificate of competence. All vehicles you buy will also need to be parked, and depending on the type of vehicle you choose, the vehicle stand may be less costly or more costly. Utilities are also not always present, depending on where it is you park, and for which type of vehicle the stand is.
Original vehicles
travel trailer / caravan
example: http://www.messynessychic.com/2014/04/16/10-vintage-trailers-sale-just-in-time-for-a-summer-road-trip/
Price: around 10 000 USD
minivans / minibuses / campervan RR-type / motorhome class B
Price: between 5 000 and 10 000 USD
See also: http://en.wikipedia.org/wiki/Minibus
See also http://en.wikipedia.org/wiki/Campervan#Rising_roof_.28RR.29
campervan type A / motorhome class A / motorhome class C
Price: between 20 000 and 100 000 USD
See also: http://en.wikipedia.org/wiki/Motorhome
large buses and schoolbuses, example:
Price: between 5 000 and 10 000 USD
See also: http://mentalfloss.com/article/52933/15-creative-converted-school-buses
Liveaboard sailboat
Price: around 15 000 to 20 000 USD
Customized vehicles
Camper bike example:
Price: can't be found/bought via eBay, only made yourself
See also: http://www.kevincyr.net/index.php?/project/camper-bike/
DIY trailer / DIY caravan / tiny house on wheels
example: http://www.fourlightshouses.com/
Price: between 10 000 and 20 000 USD
The truck camper / camper shell truck
example: http://www.theshelterblog.com/chris-bradys-truck/
Price: around 10 000 USD with pick-up truck underneath, around 5000 without pick-up truck
Housetruck
example: http://tinyhousetalk.com/1999-sterling-housetruck/
Price: can't be found/bought via eBay; (4x4) military trucks cost around 5000 to 10 000 USD
Houseboat / pontoon houseboat
Price: 10 000 to 20 000 USD or more
