i didn't want one either, really, but i was surprised how great my brother's was. i really wouldn't have guessed it was modular by looking at it inside and out.
hope you find the house of your choice. ceiling insulation is good too. if the house doesn't have it, put some in. it will save money (again on heating and cooling). another thing i've learned is that some things that bug you a little, will bug you a lot when you move in. for instance...there was a spot for the fridge in our new house on the far right of the kitchen. i said to my hubby, 'how are we going to clean out the fridge, when we can't open the door farther.' he said, 'we'll change the door on the fridge.' do you think the door on the fridge is changed. noooo. i've been trying to squeeze out the shelves on the fridge for some time, but couldn't get the vegetable bins out. so, there i go, baking soda and a little water and washing it in the fridge. i don't like that because it is a constant problem. why couldn't they put the spot for the fridge in the middle of the kitchen or at least a cabinet apart from the wall? bad planning.
that's one of the few things i don't like. most things are great. oh, except for the tub. they always LOOK big, but get into them (especially with two people) and you're cramped for room. sit down in one with your girlfriend and see if you feel comfortable. most bathrooms don't have a big enough tub even for one person. that's because they come in a horrible standard size. (for short people).
last thing that i can think of, is make sure the dining room has enough room to walk around the table! and that you can close it off from the kitchen (or has a wall or doorway). it's a hassle to always have the kitchen spotless when you entertain. very NICE to have it separate - and way for guests to walk from living to dining room. we had our dining room closed off from the front entry way (there was door there originally). i didn't like it because i didn't want the dinner to get cold (in winter) from cold air blowing in . so you walk in entry, then to livingroom, then to dining. much more formal (and surprises people when they see the table) rather than seeing everything at the door.