I check the pics, download them, blow them up and focus them to get as much info as I can. Sometimes I've emailed the seller for additional pics. Even then you don't always see all the defects.
Shipping is an integral part of the purchase price. I check the price of the item, or the starting bid (knowing that will probably increase a bunch), then check the shipping costs. Many times I've found the shipping far exceeds the cost of the item. At that point I re-check locally and if I don't find what I need (want), I have to decide if I can afford the total cost, or if I have to do without.
Lately, I've been doing without a lot. And I think that will become the norm rather than the exception. Prices are going up far faster than our abilities to pay.
The one thing I will say is this. So far the shipping costs are generally less than the gas to get the item. When the gas is cheaper, or I'm after a treadle or machine the seller won't ship, I usually declare a road trip.
I'm do for one now.
Joe