I operate from Benllech on the Isle of Anglesey on quite a regular basis from my caravan. I use a Yaesu FT-817ND with upto 30W on 2M via a Microwave Modules linear amplifier and 5W on 70cm if you have a 30W 70cm Microwave Modules linear amplifier for sale please email me !!. Antennas are mounted at around 12 feet and are identical to at the home QTH on 2M Diamond A144S5 and on 70cm Diamond A430S10 these antennas are great value for money and are of superb build quality, their full spec is on the home QTH antenna page.
Take off to the North thro West is perfect with only the sea in front of me , to the South East isn't brilliant with the Snowdonia range being in the way although the Wrotham beacon on 2M is Q5 on a HB9CV and the WSJT6 transmissions can be decoded on a halo so all's not too bad there .
GI and EI no problem and to the due south is not bad with only the topography of the island getting in the way.
I tend to only operate on SSB so please listen for my CQ calls from GW on 144.300Mhz and 432.200Mhz although I do tune both bands on FM for SOTA stations in the Welsh mountains.