This is the list of supporting docs from the E-visa application. You do not need to answer both financial questions, you can give income under question 4 or capital in question 10, best to think in terms of the 12 month extension, equivalent of 400K baht.
You must upload something for every question so where you may not want to, you can write something on a piece of paper, take a photo and upload that.
For question 9 you can get your wife to send a note on Whatsapp or something with address and tel no and upload that. Good luck.
Official Website of Thailand Electronic Visa_4.pdf