BGP Source & Destination Traffic Load Share

Source and destination base Traffic delivery.
Achieve
1.All internal traffic and client traffic pass through via ISP A
2. 10.28.20.0/24 source route Via ISP B for outgoing traffic
3. 166.24.10.0/24 traffic pass through via ISP B for incoming traffic
********************** Config **************************
Router 1
R1:
router bgp 4500
no synchronization
bgp log-neighbor-changes
network 1.0.0.0
neighbor 210.26.12.21 remote-as 4500
neighbor 210.26.12.38 remote-as 4500
neighbor 210.26.12.38 route-map Test in
neighbor 210.26.12.42 remote-as 4500
no auto-summary
!
!
access-list 1 permit 166.24.10.0 0.0.0.255
!
route-map Test permit 10
match ip address 1
set weight 100
!
route-map Test permit 20
!
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Router 3
R3:
router bgp 4500
no synchronization
bgp log-neighbor-changes
network 3.0.0.0
neighbor 88.88.88.1 remote-as 100
neighbor 88.88.88.1 route-map Test1 out
neighbor 210.26.12.22 remote-as 4500
neighbor 210.26.12.22 next-hop-self
neighbor 210.26.12.29 remote-as 4500
neighbor 210.26.12.29 next-hop-self
no auto-summary
!
access-list 1 permit 1.0.0.0 0.0.0.255
!
route-map Test1 permit 10
match ip address 1
set as-path prepend 100 100 100 100
!
route-map Test1 permit 20
!
!
*********************END*********************
Note: ( LAB 1 Diagram for Reference)