What did Bil'a mean when he said "Hin'ni Holech le'Ami" (and not 'li'Mekomi')?
Rashi: He meant that his status had been lowered to the point that he was on a par with the rest of his countrymen.
What advice did he offer Balak?
Rashi (citing Sanhedrin, 106a), Ramban #1 (citing Rashi) 1 and Targum Yonasan: He advised him 2 that, since the G-d of Yisrael hates prostitution, they should set up shops manned by prostitutes selling food and drink at cut prices, thereby attracting Yisrael to go and buy from them. 3 They will then eat and drink and become inebriated. be intimate with them and deny their G-d. 4 As a result, in no time at all, they will be handed over to Balak and many of them will die.
Ramban #2: He was telling Balak the plan that Hashem had in store regarding what Yisrael would do to Mo'av in the days of Mashi'ach.
And what does the latter half of the Pasuk then mean?
Ramban #1 (citing Rashi): Bil'am actually had in mind to inform Balak that, in the days of Mashi'ach, Mo'av was destined to fall into the hands of Yisrael. In the meantime however, he advised him what Mo'av was able to do to cause havoc to Yisrael. 1
Targum Onkelos: Bil'am was telling Balak that in the days of Mashi'ach, Mo'av is destined to fall into the hands of Yisrael.
Targum Yonasan: The advice concerned the present. Eventually however (in the time of Mashi'ach), Mo'av was destined to fall into the hands of Yisrael.