Depends on the space you have available. Either a few high end machines or more value oriented.
High End:
AFMr (7.5)
DI (8)
Adams Family (5.5)
NGG (4)
Value if you have enough space:
Genie ($1200)
EBD ($2000)
Taxi ($2000)
Whirlwind ($3200)
Joker Poker ($1500)
High Speed ($1200)
Stargate ($2000)
Judge Dredd ($2500)
EMs
C37 ($1600)
Royal Flush ($800)
Flip Flop ($800)
Night Rider ($800)
Abra Ca Dabra ($1500)
Big Hit ($1000)
That's 14 value machines for $22100 which leaves you with $2900 for shipping and some locally. If I had the space I would go for the value option. If space is a problem I'd go for high end or some combination thereof. AFMr and DI are the 2 best in my book and then some value machines.