This project for DIYer is based on the Q20 circuit but it can give you power level greater than 50W.
The top PCB is the Power Amp you get 2 off these the bottom PCB is the split psu board for the power amps, the 2 circuit boards are toys for the kid and are a FM TX low power device. Again it come with circuit diagrams and a BOM. Cost is 100 +P&P