找數 is the combination not 數算, and I think it means you're asking someone to pay back what they owe (different from what this link says is the definition/translation below (since it is a different situation, not ordering or calling for a bill/check)). LA is the just the final particle 喇, I believe.
[www.cantonese.sheik.co.uk]
影低 I have no clue, "take a photo" is what Cantodict says it is.
And also, there seems to be a lot of extra characters in this sentence.
本來想係佢搵佢出黎影低佢但太高難度, 都係偷圖找數算LA
I think you could take out some things and make it into
本來(係）想搵佢出嚟影低但太高難度，都係偷圖找數算LA
[www.cantonese.sheik.co.uk]
影低 I have no clue, "take a photo" is what Cantodict says it is.
And also, there seems to be a lot of extra characters in this sentence.
本來想係佢搵佢出黎影低佢但太高難度, 都係偷圖找數算LA
I think you could take out some things and make it into
本來(係）想搵佢出嚟影低但太高難度，都係偷圖找數算LA