This depends entirely on the renovation project itself. If you are fixing up a one bedroom flat in London or any urban area and the flat is in relatively good condition to start with, costs can be kept to a minimum with a relatively small budget. If, on the other hand, your project is renovating a derelict Victorian stone barn in the countryside, then your costs are clearly going to be much higher. Make sure you budget properly and have funds available before finding a property to renovate.