Building your house, but always running out of Iron Ingots and Goat Horns for those accursed lights? Need spare furs, glass, straw and ore, and not to mention children's goods for your new adoptees? 

Never fear, for your new home comes with a specialised Khajiit who deals exclusively in these items, so you no longer need to scour Skyrim for them. 

-Kanaihaz will be at Lakeview Manor, dressed in his resplendent outfit. Useful at dual-wielding, he can slice and dice if you mess with him. 
-J'bytinz is staying at Heljarchen Hall, a modest outfit, but don't let her lack of weapons fool you. She is fully trained in magecraft and can pack a punch. 
-Gut'koyn has chosen to rest at Windstad Manor, an older warrior used to hunting, his intimidating stature beguiling his archery skills. 

All merchants will be at your beck and call 24/7 inside your new home, wherever you choose to build it. 

Once you have purchased your property, you always have enough to build the first home, and then, your merchant will be waiting inside. Don't mind them if they choose to take a nap or eat a little food and drink while you finish furnishing your home. 

FYI, this is my first time creating a mod. Will update this when I learn more about path-making, and even a way to dismiss them directly if you don't like them hanging around the house. Reviews and ratings appreciated.