I use spreadshets that I wrote for my domains.
Sheet 1 (or file 1)
Colum names:
Domain
extension
reg date
exp. date
days to left exp.
months to left exp.
age in year with one decimal
website or domain (I am webmaster, most of my domains are established websites)
seo "bad/renew/perfect" based on the date left to renew
DA
PA
MOZ
Alexa
GD value
Domain "Renew or don't renew" based on GD value (for undeveloped domains that are listed for sale)
Price "min and max columns" based on GD value
Actual price
% : Actual price / GD value
Drop: Days left to drop or available to register since x days.
Sheet 2 (or file 2, I use a different file as the list is big): Shows me drop dates of the domains which I watch, how many days left to drop. I check this daily.
Sheet 3: Rising my domain prices periodically, includes a URL column to click to update the price using API.
Shows a calculated price that must be updated (increased) today by different % based on different price margins. For instance if the original price is between $200 and $400 it will rise by 50% per year. The result shown is for today, changes each day when I open the spreadshet. Prices incrase by 10% if the original price is between 10k - 15k. There are 7-8 different price ranges and % value. Result is rounded.