I want to put gravel area to park my 10x6 ft trailer on the side of my home on top of a grassy area not much monies to spend what kind of gravel a little how much
Assuming that you're in the US, I would recommend "base" gravel (this is the same material used for driveways). It compacts well and does not rut, if installed properly. Typically, you would need at least 6" of base, compacted. The "materials" calculation is 1 yard of material covers 100 square feet of area 3" deep (not compacted). My experience is that 3" non-compacted gravel yields about 1.5" compacted gravel. Given this... you have 60 sq. ft of area, which equals approximately 0.5 yards 3" deep, non-compacted.
So - 1 yard non-compacted gravel would yield 3" compacted gravel. You need 6" compacted, so you should need about 2 yards of gravel (maybe less). Your gravel supplier should be able to give you a more accurate total. If you do this project yourself, you can compact the gravel either with a manual "stomper" (possibly our own slang), which is alot of work, or a plate compacter (a power tool).