Auction bid frenzy!!!

I am a newbie to coin collecting but auctions are also very new to me. I am not a rich person and I have found out that I love coin collecting. I know there are a lot of coin dealers and stores where one can obtain what they want but I have found the autions most reasonable if you know when to stop bidding and wait for the next one to come up and try again. Has anyone come up with a reasonable percentage of retail as a bid where with patience you will eventually get what you want because my anxiety to obtain a coin seems to overide my common sense and my wallet and sure enough I could have gotten something at a lesser price. I want to be a sucessful collector and feed the kids too. I have never had a hobby before and the excitement of this is great. I am 61 and still have youngins. I accept all advice except to stop collecting. Thank you.