Across:
1 Does a deal with the man downstairs (devil) (SELLS ONE’S SOUL) for state (= homophone indicator) holding prisoners (‘cells’ = ‘sells’ = SELLS) and individuals (ones = ONE’S) with spirit (SOUL) (SELLS ONE’S SOUL)
10 Divorcee (EX-), for example (e.g. = -EG-), loses the head (f) at garden party (‘fete’ without ‘f’ = -ETE) (EXEGETE) with the sort who can make sense of texting? (EXEGETE),
11 Furlong (-F-) is taken in by Rocky (= anagram indicator) O’Brien (Obrien = BON-IRE) (BONFIRE) producing The Inferno for an open-air audience (BONFIRE),
12 In a timely fashion, is behind (LATE) both sides of labour dispute (both sides of ‘LAbour DispuTE’ = LATE),
13 Wins over (SELLS) all sides today (‘sell’ on all sides of today’s grid = SELLS),
15 Pickup illegal bit (‘pickup illegal’ bit = PILL) from Tablet (PILL),
17 Is that the spirit? (RUM) Trump abandons those on the border! (‘tRUMp’ abandons those on the border/side = RUM),
19 Backing (= reversal) those in 20 down (‘fir’ = -RIF-) consumed by stout (fat = TA-F) (TARIFF) – the imported costly type (TARIFF),
21 Kind (DECENT) of in good taste (in good taste = DECENT),
22 Attic in (attic in) building (= anagram indicator) (attic in = TITANIC) is huge (TITANIC),
23 Discovered in Ypres, a reasonable (discovered ‘ypRES A REasonable’ = resare) retrospective (= reversal indicator) (resare = ERASER) aiding students to eradicate mistakes (ERASER),
25 That’s settled (PAID-UP) – relative (PA-) is the one (-I-) to party (Democratic Unionist Party = -D-UP) (PAID-UP),
27 Revolutionary (= reversal indicator) hiding in Easter Island (hiding in ‘easteR ISland’ = ris = SIR) is an advocate of the class system presumably? (SIR),
29 Take a part (take apart = UNDO) setting up (= reversal indicator) in neighbourhood nursery (in ‘neighbourhoOD NUrsery’ = odnu = UNDO),
30 Nutty type (PECAN) of writer (PE-N) takes in most of (p) Cork (‘cap’ without ‘p’ = -CA-) (PECAN),
31 Refers to Africa (AFRO) backing (= reversal indicator) what’s contained in minor facility (contained in ‘minOR FAcility’ = orfa = AFRO),
34 Cross (MONGREL) mineralogists abandoned as it is (‘mineralogists’ abandoned ‘as it is’ = mneralog = MONGREL),
35 Renaissance man (Leonardo DA VINCI) produces French wine (French ‘wine’ = ‘vin’ = VIN-) integrating fresh (= anagram indicator) acid (acid = DA -CI) (DA VINCI),
36 Sounds like (= homophone indicator) somewhere wine is sold (‘cellars’ market’ = SELLERS’ MARKET) when the dealing is at its most expensive (SELLERS’ MARKET).
Down:
2 Oriental (east = E-) reader (-LECTOR) (ELECTOR) gets to decide who goes to the park? (ELECTOR gets to decide who goes to The Park as President),
3 Ran away from Ireland (‘ran’ away from ‘Ireland’ = ield = LIED) and took to fiction (LIED),
4 It’s key (OPENER) for one of those dealing with deliveries early on in the field (in cricket called an OPENER),
5 Turns up (= reversal indicator), research site (lab = -BAL-) divides Frenchmen (MM = -M-M) initially eager (initially ‘Eager’ = E-) (EMBALM) to use preservatives (EMBALM),
6 Carol (SING) is (is) upset (= reversal indicator) (is = SI-) getting a poor grade (No Grade = -NG) (SING),
7 Exploit (UTILISE) routine at the centre (‘roUTIne’ at the centre = UTI-) with silly (= anagram indicator) lies (lies = -LISE) (UTILISE),
8 Faints on the pitch, we hear (= homophone indicator) (‘faints’ = ‘feints’) (feints/bluffs on the pitch = SELLS THE DUMMY), and in the shop? Window dresser does it when model is no longer needed! (SELLS THE DUMMY),
9 Make money (SELL AT A PROFIT) in market (SELL) getting American (A-) with faucet (tap = T A P-) to go to unfinished (d) bar (‘rod’ without ‘d’ = RO-) to install (-FIT) (SELL AT A PROFIT),
14 Fool (LUNATIC) boss (= anagram indicator) in a cult (in a cult = LUNATIC),
16 Quite a lot (OFTEN) of French toast has no starch (‘French toast’ has no ‘starch’ = fento = OFTEN),
18 State once again (RECAP) takes rap (R-AP) covering up ecstasy (-E-) at college (-C-) (RECAP),
20 Irishmen (Irish ‘men’ = FIR) in Trim (m) business (‘firm’ without ‘m’ = FIR),
21 Bottle of Bacardi punch (bottle of “bacarDI Punch” = DIP) for those who like their sauce (DIP),
24 Doctor/ (= anagram indicator) /dental (dental = AL DENT-) healthcare at the foundation (‘healthcarE’ at the foundation = -E) (AL DENTE) and firm – just as the consumers like it (AL DENTE),
26 Cross Swords (cross swords = -FENCE) after (= positional indicator) a fair amount of (half of) the demo (half of the ‘DEmo’ = DE-) (DEFENCE) for protection (DEFENCE),
27 School (S-) magazine (Elle = -ELLE-) references introduction (‘References’ introduction = -R) (SELLER) to Merchant of Venice, for example (SELLER),
28 Groundsman gets rid of guns (‘groundsman’ gets rid of ‘guns’ = RANDOM) with scattershot? (RANDOM),
32 Some characters fool around (some characters ‘fooL AROund’ = laro), backing (= reversal indicator) (laro = ORAL) what’s not a written tradition (ORAL tradition),
33 Head off (avert) briefly (t) (‘avert’ without ‘t’ = AVER) to say it’s so (AVER).