I am making a Dear Jane quilt and - whilst I haven't worked out exactly hours and costs - I have kept a diary. I started my DJ journey in 2007 - and have done lots of other projects in between - Every time I complete a block I write down the name of the block, the date, what colour fabrics used and keep a running total of how many tiny pieces of fabric used in that block. I.E in block C7 I used 57 pieces - yes fifty seven - and the blocks are 5" unfinshed.
My DH then takes a photo and updates it onto my design wall - link attached here at the bottom ---- and if you'd care to have a look you can click on any block and it will enlarge it- I hope my daughters will look at this in years to come.