Advertising Layout Question

[AlexisMedia]

I use AdSpeed for my adserver. I think this appears to be no problem accept for design factors.

On the home and thread view (not post view) I want a row of 140x140 ads all the way down the right side. Only problem with this (haven't done it yet but theoretically) is that I'd need set dimensions from the start right?

I mean, if I open up a brand new forum area then there will be no threads and room for maybe one or two 140x140 ads whereas another forum area with more threads might have room for 10. Is there a way to make this grow automatically to accommodate for these size variations?

On the homepage I will have hidden areas pending on the level of subscription (I think that's possible) but again... for most people they can only see 1/3 of the forum for free so how can I have the ads extend longer on the page if it's a paid member with more access in turn revealing more forum areas?

Thanks and please let me know if what I said is not clear in any way. Thanks!

--------------- Added [DATE]1292907284[/DATE] at [TIME]1292907284[/TIME] ---------------

Thinking about it. Could I just setup tabs for each level of forum access (as setup here tab wise) and then have the heights on each of those pages preset and displaying the ads. Only they won't be able to see the actual forums unless they have that level of access?

Does any of these ideas make any sense to anybody? Please let me know so I can clarify if needed...

Thanks!