little advice please

[Revine19]

How much weight can an inexpensive bicycle support, I'm overweight and want to ride for exercise and fun?

I am just over 300 pound mark. i am 19 years old and little over 6ft

prefer mountian bikes and if you think of anything cheap its a bonus

 

[vspa]

cro-moly is a breed of steel that is cheap and strong, i would also buy a seatpost of the same material, you will be allright, look for a big saddle too, get yourself some quality tires and quality inner tubes that can be inflated into high pressure, that would be a nice upgrade for a cheap MTB in your riding situation, the heavier the rider the more air pressure needed,