Balance the books?

What is one persons junk is anothers treasure.As you may have gathered my dads hoard of books are gathering dust. A few days ago i found a book which appears older than my dad. Its called "More English Idioms for Foreign Students" by A.J.Worral. It is the 2nd edition from 1954, published by Longmans with the old logo (they publish a lot of revision guides of which we have in abundance). The terminology is probably dated but this would be ideal for "TEFL- Teaching English as a Foreign Language".Anyway, this got me thinking, books older than my dad might be worth something......
A contact list of antiquarian bookseller including websites are available at city libraries are a  good starting point to find out the value of rare or out of print books. One website will even help set up a booksellers website from £24 a year!for further details look at ukbookworld.com and the following
http://www.bmcole.co.uk/oldbooknews/yourownwebsite.htm

I haven't been able to find how much the idiom book is.  You hardly going to make a killing on this. (idiom for "make money £ which i have just checked is an idiom used since the 50's).Here a few tips if you decide to go down this road:

1. Compile what you are willing to get rid of make a list. Use Excel Spreadsheet
2. categorise them according to theme e.g if books educational, language,travel etc.
3. Get them valued. A recent book you can just check on ebay,amazon or abebooks to find out how much others are selling it for. If an old book check online or with a secondhand bookseller
4. Description and condition of books.
5. Cost for sending by post. You can either weigh and measue thE dimensions and then check with the royal mail (UK) website.for each item. Will you send by first class or second class?
6. Organisation- How will your books be stored and will you know where they are especially if you have thousands of them. Group according to genre/topic. Nothing would be more frustrating if a buyer had paid but you couldn't find the item or worse it had fallen in to your pets possesion.
7. And this is me being very "grown-up and responsible" you would have to declare your business as self employment to HM Revenues and Customs aka the "taxman"

I am interested to find out  if anybody sells second hand stuff on the web and HOW they manage to do it efficiently as i can see the above being time consuming.
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