at the moment it's not such a great idea, what with how the market is - especially as its last one in, first one out. however, estate agency is an unregulated business, so theres no qualifications involved, but you do need to be a good salesperson and negotiator. i work in a similar business (property investments) and it is very cut throat, especially as the majority of an agents earnings will be commission based. you also need to have very good local knowledge and be aware of current market conditions. day to day you will be negotiating with vendors as well as buyers, and speaking with solicitors, valuers and conveyancers so a basic understanding of the legal process of purchasing property would be very useful. i struggled to work in property investments before i understood the mortgage process, so i spent a few hours a day with a company of mortgage advisors just to see how it all works. why don't you offer yourself for work experience for a couple of weeks to see if its for you? if you pick perhaps the longest established / most popular agent in your area, maybe they'll even offer you a job at the end of your work experience. definitely try to pick one that has a lettings department, as rentals have shot up recently as mortgages have become increasingly difficult to obtain.
personally, i'm just trying to get out of property...it's really, REALLY tough right now to get business through (but i deal with investors more than residential purchasers). obviously people are still moving, buying and selling, and the stamp duty threshold has recently dropped, meaning first time buyers have a better chance than before of getting on he ladder, so its not all doom and gloom!!
i hope my little essay has helped in some way. good luck!