yes you can do what you want. I would have them install the house first. Then go online and order a basic SD receiver. Easy to activate and set up by yourself. They normally won't install in RV's.
Note: when you travel and are out of your local channel area, you won't get local channels on Directv. You can scan for local digital channels with a digital TV or digital converter box.
Note about receivers going inactive after non use for 30 days. I reset my receiver online. I like it much better than calling the toll free number. Either method is easy tho.