You've only been a member for one month. Why not try out a one month premium membership for $14 before you mortgage the house?
At any rate, you want a lifetime diamond membership for the equivalent of three years of diamond membership? That seems a little cheap. I doubt if they would even respond.
If you are serious, why not make a serious offer? Send them $2,000 and see if you get a response.
Being a passionate chess player, I would be happy to oblige to a one-time lifetime membership fee of $300 with full access including all the additional previleges that maybe offered by chess.com in the near future.
I will save every penny I've got just in case chess.com changes its mind. I will stop drinking a cup of gevalia espresso or glass of chalkhill chardonnay per day to save $27 per week. I will stop watching movies to save $8 per month. I will stop using my smart phone just to save $60 per month. I will stop buying cosmetics to save $50 per month. I will stop buying new clothes and any unnecessary materialistic desires of a typical female.
Whatever it takes, I am challenging chess.com to give away a chance to purchase a lifetime membership fee for a few select individuals who are passionate enough to keep this awesome website going!