Everyone should play at their level. Deposit what is comfortable for you. If $50 works - great!
I started playing online poker at the beginning of 2001 when there was mostly play money tables. You had to wait for 45 mins to get a sit n go filled....can you believe that.
After 6 months to a year I finally deposited $100 bucks using a seperate online bank account.
I played mostly ring games and a few sit n goes. My stack went up and down...then right down to ZERO. I said I wouldn't deposit more money. That I should be able to turn it around. From zero, you say? Yes, from zero.
Freeroll mania. That's what I did. I placed in the top 10 in several 2000 players freerolls
that gave me a few bucks. I entered a $1 tourny and came in 2nd for $163. Not much I know but it sure felt good. Well actually I was rather pissed off that I didn't beat the guy heads up, but that is another story.
I have devoted a lot of time to sit n goes now. I play on 3 different sites. $5, $10 and $20 tournies. I am up overall about $2500 since I started. Not big money but it works for me.
I have been down to zero twice.
My advice... (take it for what its worth)
Don't just reach into your pocket for another 50 bucks, try to use some of your skill and knowledge. Take a stab at the freerolls. Who knows you may win $7 and turn it into $1000...