"What are you getting into"? A whole bunch of fun ! " The problem is your wife"? That can be a problem , your thought about a little at a time works for my wife too . Over the last 12 years (that's when I started) I have built around 15 bikes , lost money on every one of them . So my wife made a rule , start another bike , sell one first . I'm having a little trouble with that , I'll be OK .
Paint is one of my favorite things , my problem is I don't have a good place to to paint .
One thing I wish I had done at the start was to get a work stand . I like tools , bike tools are a little different then most regular tools , to start with I got headset wrenches , bottom bracket wrenches , and wheel cone wrenches , a chain breaker and Allen wrenches . You will need a lot more but that's the fun .
Good luck and keep us posted , Mark .
Some of my bikes
https://www.pedalroom.com/bikes/search?q=markwesti