Hello,
Regarding the VHF part, what is the center frequency, required Bandwidth, required return loss (or VSWR), is it used over a metallic or non-conducting structure (for example vehicle), input power (in case of transmitting), polarization, etc? When you have the choice, it is best to operate the antenna over a metallic plane (for example roof of vehicle).
The UHF part is the easy one, the VHF maybe difficult depending on desired useful bandwidth. As your maximum height is 0.3m, the VHF antenna may be small with respect to 0.25lambda. In such cases you need special tricks to have reasonable useful bandwidth.
Regarding the Yagi, there are many designs and good building plans. Look also at radio amateur sites (HAM radio), as your UHF operating frequency is close to the 70 cm (430 MHz) band. You can easily scale good 70 cm designs to your frequency. Also here you need to compare your requirements (gain, F/B ratio, bandwidth at certain RL/VSWR, mechanical requirements) with the various designs. The "problem" with yagi antennas is that you have lots of parameters, so you can optimize for maximum VSWR bandwidth, Gain at center frequency, Gain over the full operating band, but not all at the same time.