need some quick battery advice

[dcastillo]

so long story short, I busted my butt at work and really impressed a customer who wants to personally thank me. He knows about my hobby of building a cart for my kids and wants to buy some batteries for me

currently I use 4 of these guys that I choose for the price and jsut to get me going, which they seem to work great for (25 min ride time with my 800W motor)
http://www.chromebattery.com/12v-9ah-sealed-lead-acid-sla-t2-connector.html

I was planning on getting something more like this for my final setup (about $40 each)
http://www.chromebattery.com/12v-18ah-sealed-lead-acid-sla-battery-t3-terminals.html

but my customer just said he was planning on spending $100 or so on each battery
not that I want to take advantage of him, but what battery would you recommend for sub $100? since Ill be using 3 or 4 of them, I probably dont want massive batteries due to the weight.
I was thinking something like this
http://www.chromebattery.com/12v-35ah-sealed-lead-acid-sla-nut-and-bolt-connector.html

obviously $100 wont buy a yellowtop or LiFePo, are there any good ideas in the middle

 

[dcastillo]

or would I be better off buying some AGM batteries like these
http://www.vmaxtanks.com/servlet/the-Power-Sports-Series/Categories

 

[landuse]

Hang in there, you will get some advice soon

 

[ML-TOYS]

Theres some factors you need to consider like how much room do you have and how much more weight you want to carry.
Personally i would get the 18ah ones but twice as many. Then i would have 2 battery packs to run. Run one down then toss on charge while using the second one while the first starts getting charged.