i suppose it depends if your yachts for getting into racing as a starter or its for a few hours at the weekend, if its for racing you will proably end up spending a fortune on building a class racer or buying one semi or pre- built anywhere from £300-500+ and thats no joke!
Its not that expensive to build a boat to any real size.. i mean a sheet of 3mm-5mm marine ply here is £11 for a 8x4! thats enough to knock out 2 boats... planking material from shops £2.50 for 5m x5mm strips so £10 there so far ya up to £22. GPR if your going to use it .. further £20-40 pending on matting and amount, then sails £10 for a kite shop .. only real expense is radio gear decent servos and receiver £50 job lot of ebay maybe. then make a keel or buy one £10 paints.. £20 .. total.... £150 roughly.. how much is the micro Victoria?
remeber building it yourself means not looking for spares when it goes wrong.... and when something does go wrong you know every inch of your boat and will be able to fix it better, not only that you can spread the cost of your build over time lowering that lump sum in one hit