Need to develop an Electromaget-based device with variable force (willing 2pay4help)

Hello everyone! Boy am I glad this forum exists!
I have an idea in mind for a device that I cannot find anywhere but would be happy to develop it myself, had I known this field as much as you do.
I saw some unbelievably bright-minded people when reading threads, I am sure you guys can help me with my idea.

Basically I need to develop an electromagnet with variable force that I could attach to metal surface (without the magnet touching the surface) to influence it. I need to be able to regulate the force of the influence (so that I could use it on metals with various thickness). I could do it just by moving the magnet away from the object, but I would rather have some turning knob on a control unit to regulate it while having the magnet fixed to the metal at a set distance. What really is important is that I want the magnet to apply electromagnetic force at the intervals (not constantly), so that when the magnet influences a part of the metal where it is applied, it acts as a small hammer, but from the opposite side. I also need to be able to control the focus of the force, if it is at all possible.

If you think you can help me with developing it, I would be happy to pay you. We can meet in Phoenix area or I don't have a problem working with you remotely.
Of course I would highly appreciate any advice or information from fellow members.

Thanks very much in advance for viewing this post, you guys have an awesome forum, keep up the good work!

hey insight i think that u r making a gravity free room
(1). make pwm for ur solenoid __mosfets better. easily implimented by small pic mcu with switcher
(2).focous of force is by ur solenoid pole ::to the plate it likes to kiss
(3).make some stepper motors adjustment for angle something
__________once a time when in childhood i make a solenoid hold in over two inches from ground
and by pwm with pic with opto ,,my wish to float a coin of iron in air
hehe i want to show my dad gravity demystified

No actually I am trying to bend metal with magnet, for car body repair. My idea is to fix hail damage with strong magnet. Thanks for the advice though. =)