. Get up to level 16 Elven residences, you are talking about using all three tier goods and a heck of a lot of supplies to get it there. Sometimes you may only need a small building to fit what you are doing and if you take away that option or factor in the cost per building at each level unlocked, it may make a lot of people unhappy.
Just as a side note. To build a house from scratch and upgrade to level 16 costs much more than if you were able to build it directly once you have researched that technology.
Just my opinion. You should be able to choose what size of house you want, once you have researched that specific technology. ie When I have researched Advanced Residencies I should be able to choose to build a level 4 directly if I so choose. Or if I have lack of space or supplies etc. Build a level 1. The same for when I complete research on level 8. It is logical that once you have researched the technology you should be able to use it directly.
For example. If you have researched Level 16 residencies To build from new and upgrade to that level will cost in total 259000 coins 33690 supplies plus all the other scrolls, crystals etc. Perhaps it would be fairer if you had a choice to buy directly for a certain cost of coins, supplies etc. Lower than the upgrading route. Or you can build smaller and upgrade. It should be a choice. It is like when I bought Ableton Live. They have 3 versions Intro/Lite, Standard and Suite. If you buy Suite direct it is €599. If you buy Intro at €79 then upgrade to Standard then to Suite you end up paying more.