L._.
I definitely agree about the materials. We bought a new modular home in California. It was awesome when we moved in. But in the 2 years we were there, the carpet deteriorated quickly. It filled bag after bag as I vacuumed, always just disintigrating and fuss balls everywhere. Steam cleaning was terrible as the fuss balls clogged my cleaner and ruined it.
The cabinets were so cheap that our fingers wore away the finish just by opening the doors. The steam that rose up from the dishwasher had the cabinet doors in the vascinity swelling up.
The plumbing was fine, bathrooms nice etc. They did a decent job of putting it together and the seems didn't show while we were there. But we needed to sell it when it was only 2 years old. We had to put 10,000 in it at the time just to get it back to a new feel.
I'm sure you can ask for upgrades as needed with any of the companies. Tell them that you intend to live in it, not rent it out. Make sure the cabinet doors are of a good finish, the carpet a decent grade, and definitely get a long warranty for the seems. We were told by many people that if they do a bad job, the cracks will show and show bad quick.