Market tracking calculations

Question

I am starting a market strategy with $10,000.  Every week I may be selling or buying any or all of the stocks, but will never hold more than 5.  I would like to set up automated calculations. 
The idea behind the strategy is that i originally invest an equal amount of funds into each of the original stock choices, hold for a week, then compare whether the stock is still listed at its high the next Monday.  If the stock is still on it's high, I keep it for another week.  If it has fallen off, I sell the stock and replace that/those stock(s) with the one(s) that have replaced it.  This will call for buying and selling up to 260 stocks within a year,keeping track of the cost of the trades at $7 a pop, and evenly distributing both the initial investment across the stocks and then any time more than one stock falls off the high.  I should always to to have balanced amounts invested in each stock without have to buy/sell to make that happen.
Example:  Week 1 (Initial Cash Fund = $10,000)
Stock A @ $25 a share ($2000 - $7 fee = $1993 to spend) = 79 shares = $1975 w/ a $18 remainder
Stock B @ $40 a share ($2000 - $7 fee = $1993 to spend) = 49 shares = $1960 w/ a $47 remainder
Stock C @ $50.91 a share ($2000 - $7 fee = $1993 to spend) = 39 shares = $1985.49 w/ a $7.51 remainder
Stock D @ $17.25 a share ($2000 - $7 fee = $1993 to spend) = 115 shares = $1983.75 w/ a $9.25 remainder
Stock E @ $86 a share ($2000 - $7 fee = $1993 to spend) = 23 shares = $1978 w/ a $15 remainder
Total Remainder = $96.76 stays in Cash Fund
(I would want the calculations to tell me how many shares I could buy of each stock as well as keep track of any remainders)
Week 2 (Cash Fund = $96.76)
Stock A, B, and C all remain on their highs
D fell off the list and needs to be sold @ (17.10 * 115) - 7= $1959.5  (loss of $31.25)
E fell off the list and needs to be sold @ (88.40 * 23) - 7= $2026.20 (gain of $41.20)
Cash Fund = $4082.46
Buy Stock F @ $15 a share ($2000 - $7 = $1993 to spend) = 132 shares = $1980. w/ a $13 remainder
Buy Stock G @ $116.5 a share ($2000 - $7 = $1993 to spend) = 17 shares = $1980.50 w/ a $12.50 remainder
Toal Remainder = $121.96
ETC.
I can visualize the basics of the spreadsheet, but am uncertain as to how to add some functions or even where/how to list certain basics and I have yet to find anything that clearly shows what I what.  If anyone is willing to share, I would be most grateful.
Thanks

Answer 1

HI Gemma,
ELSE is buillt into the IF function. The syntax is IF(condition,do-if-true,do-if false)
For both buy and sell formulas in my post, the 'ELSE' part (do-if-false) was "" which means 'return a null string.
To combine costs and proceeds into a single column, you'll need to account for three conditions in the buy/sell column: Buy, Sell, and none of the above (where no choice of transaction type has yet been made). Since IF tests only for one condition at  time, you'll need to use a pair of nested IF statements. The second replaces the do-if-false part of the firat.
Syntax: IF(condition1,do-if-true,IF(condition2,do-if-true,do-if false))
Some questions:
Will you ever buy the same stock a second time? I'm looking at a way to automatically populate the number of shares sold. I've assumed that you intend to sell all your holdings of a specific stock each time you do a sell transaction, so the shares sold would be equal to the number bought in a previous Buy of the same stock. That's a simple Lookup if there's only one mention of that stock in the cells prior to the current one, but not it there's more than one Buy of the same stock (all but one of which will, in the case of repeated buys, have a matching Sell transaction, according to your description.
What happens when the cash balance falls below 2000 * the number of Sell transactions done in a specific week?
What happens when the cash balance rises? How much does it need to rise for that to happen? Knowing those would allow automating the "Available" column
The transaction fee could also be easily calculated, rather than requiring entry on each transaction. A 'fixed' fee is likely to change over time, and caution would be needed to ensure that the change would apply only to transactions (rows) after the new fee came into effect.
Regards,
Barry