I want to know what type of camshaft location is most common in most vehicles? Is it an OHV/DOHV or OHC/DOHC/SOHC
They are all common in different configurations.
OHV is most common in V style engines, since you can have a single cam in the middle of the block. This weighs less than having a cam over each head, plus the belt/chain to drive it. This is most common in large 'truck' engines that need power at low RPM.
SOHC is common on all engines. SOHC is used typically on "low end" economy engines, or engines that need to make max power at lower RPM.
DOHC is also common on all engines. These engines tend to produce power at higher RPM as most DOHC engines have 4 valves per cylinder.
First of all DOHV is not in production period.
Most cheap engines especially ones with lower capacity and power outputs use SOHC configuration like the suzuki 1.2L engine or G13B which are all sub 1.8L engines.
Also, if you take the raw count, then I would say, yes the SOHC is the most produced configuration since 90% of motorcycles in developing countries like India and Vietnam have a huge number of single cylinder SOHC configured bikes and mopeds.
The Second most Common configuration is the DOHC setup which almost all of the modern cars use and is pretty much the standard for automotive engines apart from some chevy engines.
The third popular alternative , which is dying and is in its final stages is the OHV configuration which only a few Chevy and GM engines use now a days.Needless to say that some shipping engines and electricity generators use OHV today due to its advantages and since the generators run at a constant speed OHVs do the job best.