ACROSS
 1. <cool> STANDOFFISH = (STAND OF FISH)
 9. <greed> AVARICE = A R inside A VICE
10. <wear fancy clothes> DRESS UP = D + PURSES*
11. <mix> INTEGRATE = I REAGENT* outside T
12. _T _U _D _O _R = TUDOR <house>
13. EX PRES + SWAY = EXPRESSWAY <means to travel across America>
15. B_R_A_N = BRAN <breafast food>
17. TAR _E_ = TARE <weight of vessel>
19. <security> COLLATERAL = (.o)COL LATER AL(a.)
22. <stride> TREAD = TRAD outside E
23. ON inside CART + I S T = CON ARTIST <scammer>
25. <make cliché> OVERUSE = O VERSE outside U
26. P LACE BO_ = PLACEBO <ineffective drug>
27. ST RATE GIS T_S = STRATEGISTS <military planners>

DOWN
 1. S ENGLISH* = SHINGLES <disease>
 2. <venue> ARENA = ARE _N _A
 3. DOD ←BEG← ALL = DODGEBALL <missile evasion activity>
 4. <celebration> FIESTA = (.l)FIE STA(s.)
 5. "INN CIDER" = INSIDER <member of clique>
 6. (I RIOT + HALFPENNY)* = HYPERINFLATION <sudden loss of purchasing power>
 7. MAN (N out of INFESTATION'S) = MANIFESTATIONS <symptoms>
 8. <PC> LAPTOP = L OP outside APT
14. SCOTCH EG G = SCOTCH EGG <pub snack>
16. <movie> STAR WARS = ←S RAW RATS←
18. <cervid> ROE DEER = R OED _E_ _ER_
20. RIDER outside A = RAIDER <Viking?>
21. <tailor> ADJUST = A DJ _U _S _T
24. NAPLES - _L_ = NAPES <scruffs>