From personal experience Be on site with your wife Oversee the work As nice as it sounds don't employ her aunties brothers son who builds houses. Their is a reason he's cheaper
Just going through my first 1 year extention and one odd thing they did ask for was evidence of bank account recently used Girl at immigration said just take some cash out and then put it back in the following day Did that so far so good
I did my non o 90day marriage on line Very well set out site
If you hit a snag you can stop it will give a ref number and you can just pick up where you left off So if you realise you have a doc or photo missing no problem Just return to site when you have it