Tourist Visa run

If all you need is an Exit Stamp on your passport, then it doesn't matter which border point. You can get to any border point, park your car there, get your exit stamp, wait for a while and then re-enter with the new visa.

The border point at Mezyed (Exit from Buraimi) is a good option as you can simply walk the distance between the two border points and you won't need a taxi.

Great advice, thanks.
Is the border sign posted and easy to find? I believe I must cross at Khatm Al Shakla (expats) and not Hili (GCC only)
How much will the Entry visa to the UAE cost and do I need to pay in AED?

The border points are well posted and easy to find. You can also use Here Maps App on your smartphone, just download UAE & Oman Maps in Advance so that you can use the maps offline.

Khatam Al Shakla & Mezyed Checkpoints are open for Expats.

I don't know how much the visa will cost, as it depends on your nationality. You can pay with Cards or AED both are possible.

Does anyone know if the visa from the UAE border can be renwed after 30 days at the airport?

As far as I know, visa can be renewed at any Immigration Office in UAE including Airport.

Thank you VidoDido.

I would recommend flying.

It's quicker and easier, unless of course you are up near the border.

Flying is boring and expensive. I have done it 3 times, it takes 10 hours and once you factor in the return flight, the cost of food and drink at the airport in Dubai and the visa, then taxis to and from Muscat airport to where I live.....
Have car will travel!!!

I would still nonetheless recommend flying.

I'm not sure as to why you're doing a tourist visa run and as far as I am aware the min of tourism, labour and immigration do not officially share data on this subject, so if you're doing it while waiting for clearance, for example. I understand,  but the time will come, when you can expect to get some very searching questions asked of you, when coming back into Oman be it at the airport or land border post and not from those that you would expect.
By flying, you actually show that you have certain financial advantages over those that use a car, for the very reasons you mention and this can be to your advantage.

It's more expensive as you have said.

Also your passport is beginning to fill up with consecutive 'tourist visas'

I base the above on experience.

I use to use Fly Dubai as they were  the cheapest.