Cs have 5 contracts for Bradley, Moore, Johnson Pierce, and Rondo) and a player option contract of $4M for Bass. I assume Bass will opt out. Jeff Green has no contract and the Cs have no rights, so he's a UFA. (5 contracts, $31.3 M)
Their two first round picks should net another $2.5M on a rookie scale. (7 contracts $33.8 MM).
I assume that Bass can be resigned at a BBD-like contract for $6.5 for 4 years. (8 contracts, $40.3M).
I assume KG can be re-signed at $11M for 2 years, RA can be re-signed at $7MM for 2 years, and Wilcox re-signed at $3M MLE for 1 year. (11 contracts $61.3 MM).
At this point you can sign one max contract at $21MM or a 2 contracts splitting the same amount. Depending what you do, you have 2-3 more slots for vet minimum contracts for $1MM for one year. I think Stiemsma gets 1 of those slots. (15 contracts $85+M).
That gets you into the same ball park as this year before the luxury tax. D12 could be bought in and have a great shot to win 2 crowns, but I doubt it. Better bet is to look for 2 good players at the $10MM range. A list of available FAs follows.
http://www.hoopsworld.com/2012-nba-free-agentsOverpaying height in Kaman for $10M solves one huge hole at the 5 and then get a second good player at the 2 or 3 and a vet min PG. I'd expect that JJJ and AB will be used much more next year. Big fly in the ointment is what KG does. I think Allen will continue to play and would take a small home town discount to stay in Boston (i.e., take $7M vs $8M elsewhere), but KG might retire. Tough to figure a market value on KG, so $11MM is a SWAG. KG's still a very good player, if no longer worthy of All-Star status (as is Ray and PP).