Docusign Pricing for SP Online

https://www.hellosign.com/ might also be worth a look - https://docs.microsoft.com/en-gb/connectors/hellosign/

Here are the references Adobe sent me when I signed up for a trial last year

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYHGORPF5UGK3DQPAXGCZDPMJSS4Y3PNUXXG2LHNYXWQZLMOAXXEZLGMVZGK3TDMVPWO5LJMRSXGLTIORWWYI2NKNHWMZTJMNSSELBCNFSCEORZGEYTANZTFQRG64THEI5CEODGGJSDAOJRGUWTANDCMEWTCMLFGYWTSNBQMEWTAMTDHFQTMOBXMMZTGYRCFQRHG2LHEI5CES2TKNVUW6DYLBRW6RBTG5GXIUKYL5MWS5KFMFREYZCIPJXGIX2VJJNEGYRSOIZWCQKDN46SE7I=

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYHGORPF5QWG4TPMJQXILTBMRXWEZJOMNXW2L3VOMXWK3RPO5UHSLLBMRXWEZJPNFXHIZLHOJQXI2LPNZZS63LJMNZG643PMZ2C233GMZUWGZJNGM3DKLTIORWWYIRMEJUWIIR2HEYTCMBXGMWCE33SM4RDUIRYMYZGIMBZGE2S2MBUMJQS2MJRMU3C2OJUGBQS2MBSMM4WCNRYG5RTGM3CEIWCE43JM4RDUITVIZGWKYSIPBMVMQTVMFRE45RZHBHHQUTUNFMFM4JTFVMS253EJFQTENRYGZWU623RKRZT2IT5

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYDULZPO53XOLTBMRXWEZJOMNXW2L3HN4XXG2LHNYWW6ZTGNFRWKLJTGY2SELBCNFSCEORZGEYTANZTFQRG64THEI5CEODGGJSDAOJRGUWTANDCMEWTCMLFGYWTSNBQMEWTAMTDHFQTMOBXMMZTGYRCFQRHG2LHEI5CESCXGJJEOMSEONDGY3DSIV3FAT2HPFTXKV2PGBCDSULWG5EUI5KPGU4GE2THLJJHA4ZTKU6SE7I=

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYHGORPF53XO5ZOPFXXK5DVMJSS4Y3PNUXXOYLUMNUD65R5GFTEMZTTMRREWN3XKERCYITJMQRDUOJRGEYDOMZMEJXXEZZCHIRDQZRSMQYDSMJVFUYDIYTBFUYTCZJWFU4TIMDBFUYDEYZZME3DQN3DGMZWEIRMEJZWSZZCHIRE44KWORIE6M2KLJ4USR2RMJUC223NORVUMSS7MRFTG2DBOJDHMLJNHF3DKNJRNVEDSY3HHURH2===

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYHGORPF53XO5ZOPFXXK5DVMJSS4Y3PNUXXOYLUMNUD65R5G5NG233PKBSXCZRTKERCYITJMQRDUOJRGEYDOMZMEJXXEZZCHIRDQZRSMQYDSMJVFUYDIYTBFUYTCZJWFU4TIMDBFUYDEYZZME3DQN3DGMZWEIRMEJZWSZZCHIRGMUKUOI3XC3SENEYDAWTVLA4VCRL2NNAU4U3JON2EST32GBKXOULQOBAXQZKDKIZVS4JQHURH2===

Adobe Sign | https://adobedocumentcloud.outrch.com/api/mailings/click/PMRHK4TMEI5CE2DUORYHGORPF5QWG4TPMJQXILTBMRXWEZJOMNXW2L3VOMXWK3RPO5UHSLLBMRXWEZJPORZHK43UFVRWK3TUMVZC42DUNVWCELBCNFSCEORZGEYTANZTFQRG64THEI5CEODGGJSDAOJRGUWTANDCMEWTCMLFGYWTSNBQMEWTAMTDHFQTMOBXMMZTGYRCFQRHG2LHEI5CESTWGV5GSLJUIJZTGSLWJQ3TK3K7IU3XK3DQOU3UWNKJOQZVMN2ROV4WWNTUNBFTA6BUNM6SE7I=